A four-wheel-drive vehicle is transporting an injured hiker to the hospital from a point that is 30 km from the nearest point on a straight road. The hospital is 70 km down that road from that nearest point. If the vehicle can drive at 30 kph over the terrain and at 130 kph on the road, how far down the road should the vehicle aim to reach the road to minimize the time it takes to reach the hospital? (Round your answer to two decimal places.)

Answers

Answer 1

Final answer:

To minimize the time it takes to reach the hospital, the vehicle should aim to reach the road 30 km from the starting point.

Explanation:

To minimize the time it takes to reach the hospital, the four-wheel-drive vehicle should aim to reach the road at a distance that allows it to travel at its maximum speed on the road. The vehicle can drive at 30 kph over the terrain and at 130 kph on the road.

So, if the vehicle aims to reach the road after traveling 30 km over the terrain at 30 kph, it will take 1 hour. Then, on the road, it will travel at 130 kph for the remaining 40 km, which will take approximately 18.46 minutes. Therefore, the vehicle should aim to reach the road at a distance of 30 km from the starting point to minimize the time it takes to reach the hospital.


Related Questions

You are in a room in a basement with a smooth concrete floor (friction force equals 40 N) and a nice rug (friction force equals 55 N) that is 3 m by 4 m. However, you have to push a very heavy box from one corner of the rug to the opposite corner of the rug. Will you do more work against friction going around the floor or across the rug, and how much extra?

Answers

Answer:

I will do more work against friction going around the floor.

ΔW = 5 J

Explanation:

Given

Ff₁ = 40 N

Ff₂ = 55 N

a = 3 m

b = 4 m

We have to get the distance d₁ as follows

d₁ = a + b = 3 m + 4 m = 7 m

And  d₂:

d₂ = √(a² + b²) = √((3 m)² + (4 m)²)

⇒   d₂ = 5 m

then we use the equations

W₁ = Ff₁*d₁ = (40 N)(7 m) = 280 J   (work against friction going around the floor)

W₂ = Ff₂*d₂ = (55 N)(5 m) = 275 J  (work against friction going across the rug)

since  W₂ < W₁  I will do more work against friction going around the floor.

Now, we apply the formula

ΔW = W₁ - W₂ = 280 J - 275 J = 5 J

Final answer:

When pushing the heavy box from one corner of the rug to the opposite corner, you will do more work against friction going across the rug than going around the floor. The extra work against friction across the rug is calculated to be 375 J.

Explanation:

When pushing the heavy box from one corner of the rug to the opposite corner, you will do more work against friction going across the rug. The force of friction on the rug is greater than the force of friction on the smooth concrete floor. To calculate the extra work, you can use the formula:

Extra work = (force of friction on the rug - force of friction on the floor) x distance

Extra work = (55 N - 40 N) x (diagonal distance of the rug)

Since the rug is 3 m by 4 m, the diagonal distance can be calculated using the Pythagorean theorem:

diagonal distance = √(3^2 + 4^2) = √(9 + 16) = √25 = 5 m

Therefore, the extra work against friction going across the rug is (55 N - 40 N) x 5 m = 75 N x 5 m = 375 J.

A car traveling at a velocity v can stop in a minimum distance d. What would be the car's minimum stopping distance if it were traveling at a velocity of 2v?

a. 4d
b. 2d
c. 8d
d. √2 d
e. d

Answers

Answer:

a. 4d.

If the car travels at a velocity of 2v, the minimum stopping distance will be 4d.

Explanation:

Hi there!

The equations of distance and velocity of the car are the following:

x = x0 + v0 · t + 1/2 · a · t²

v = v0 + a · t

Where:

x =  position of the car at time t.

x0 = initial position.

v0 = initial velocity.

t = time.

a = acceleration.

v = velocity of the car at time t.

Let´s find the time it takes the car to stop using the equation of velocity. When the car stops, its velocity is zero. Then:

velocity = v0 + a · t      v0 = v

0 = v + a · t

Solving for t:

-v/a = t

Since the acceleration is negative because the car is stopping:

v/a = t

Now replacing t = v/a in the equation of position:

x = x0 + v0 · t + 1/2 · a · t²     (let´s consider x0 = 0)

x = v · (v/a) + 1/2 · (-a) (v/a)²    

x = v²/a - 1/2 · v²/a

x = 1/2 v²/a

At a velocity of v, the stopping distance is 1/2 v²/a = d

Now, let´s do the same calculations with an initial velocity v0 = 2v:

Using the equation of velocity:

velocity = v0 + a · t

0 = 2v - a · t

-2v/-a = t

t = 2v/a

Replacing in the equation of position:

x1 = x0 + v0 · t + 1/2 · a · t²  

x1 = 2v · (2v/a) + 1/2 · (-a) · (2v/a)²

x1 = 4v²/a - 2v²/a

x1 = 2v²/a

x1 = 4(1/2 v²/a)

x1 = 4x

x1 = 4d

If the car travels at a velocity 2v, the minimum stopping distance will be 4d.

Answer:

4d

Explanation:

A balloon has an initial radius of 0.075 m. A circle is painted on the balloon using silver metal paint. When the paint dries, the circle is a very good electrical conductor. With the balloon oriented such that a 1.5-T magnetic field is oriented perpendicular to the plane of the circle, air is blown into the balloon so that it expands uniformly. The silver circle expands to a radius 0.125 m in 1.5 s. Determine the induced emf for this silver circle during this period of expansion.

Answers

Answer:

The induced emf for this silver circle during this period of expansion is 0.0314 V.

Explanation:

Given that,

Initial radius = 0.075 m

Magnetic field = 1.5 T

Radius = 0.125 m

Time t =1.5 s

We need to calculate the induced emf for this silver circle

Using formula of emf

[tex]\epsilon=\dfrac{d(BA)}{dt}[/tex]

[tex]\epsilon=\dfrac{B(A_{f}-A_{i})}{t}[/tex]

[tex]\epsilon=\dfrac{B(\pi r_{f}^2-\pi r_{i}^2)}{t}[/tex]

Put the value ino the formula

[tex]\epsilon=\dfrac{1.5(\pi\times(0.125)^2-\pi(0.075)^2)}{1.5}[/tex]

[tex]\epsilon=0.0314\ V[/tex]

Hence, The induced emf for this silver circle during this period of expansion is 0.0314 V.

The induced emf for the silver circle during this period of expansion is approximately [tex]\(\boxed{0.0314 \, \text{V}}\).[/tex]

The induced emf  in the silver circle during the expansion can be calculated using Faraday's law of induction, which states that the induced emf in a closed loop is equal to the negative rate of change of the magnetic flux through the loop. Mathematically, this is expressed as:

[tex]\[ \varepsilon = -\frac{d\Phi_B}{dt} \][/tex]

 The initial area [tex]\( A_i \)[/tex] when the radius [tex]\( r_i \[/tex]) is 0.075 m is:

[tex]\[ A_i = \pi r_i^2 = \pi (0.075 \, \text{m})^2 \][/tex]

 The final area [tex]\( A_f \)[/tex] when the radius [tex]\( r_f \)[/tex] is 0.125 m is:

[tex]\[ A_f = \pi r_f^2 = \pi (0.125 \, \text{m})^2 \][/tex]

 The change in area [tex]\( \Delta A \)[/tex] is:

[tex]\[ \Delta A = A_f - A_i = \pi (0.125 \, \text{m})^2 - \pi (0.075 \, \text{m})^2 \][/tex]

 The time taken for this change [tex]\( \Delta t \)[/tex] is 1.5 s.

 The induced emf [tex]\( \varepsilon \)[/tex] is then:

[tex]\[ \varepsilon = -\frac{d\Phi_B}{dt} = -B \frac{\Delta A}{\Delta t} \][/tex]

[tex]\[ \varepsilon = -1.5 \, \text{T} \times \frac{\pi ((0.125 \, \text{m})^2 - (0.075 \, \text{m})^2)}{1.5 \, \text{s}} \][/tex]

 Now, let's calculate the numerical value:

[tex]\[ \varepsilon = -1.5 \times \pi \times \frac{(0.125^2 - 0.075^2)}{1.5} \][/tex]

[tex]\[ \varepsilon = -1.5 \times \pi \times \frac{(0.015625 - 0.005625)}{1.5} \][/tex]

[tex]\[ \varepsilon = -1.5 \times \pi \times \frac{0.01}{1.5} \][/tex]

[tex]\[ \varepsilon = -1.5 \times \pi \times 0.00666\ldots \][/tex]

[tex]\[ \varepsilon \approx -0.0314 \, \text{V} \][/tex]

The negative sign indicates the direction of the induced emf according to Lenz's law, which is opposite to the direction of the change in magnetic flux. However, the magnitude of the induced emf is approximately 0.0314 V.

Therefore, the induced emf for the silver circle during this period of expansion is approximately [tex]\(\boxed{0.0314 \, \text{V}}\).[/tex]

A long, straight wire carrying a current of 380 A is placed in a uniform magnetic field that has a magnitude of 6.59 × 10-3 T. The wire is perpendicular to the field. Find a point in space where the net magnetic field is zero. Locate this point by specifying its perpendicular distance from the wire.

Answers

Answer:

The point in space where the net magnetic field is zero lies by specifying its perpendicular distance from the wire is 0.01153 m.

Explanation:

Given that,

Current = 380 A

Magnetic field [tex]B=6.59\times10^{-3}\ T[/tex]

We need to calculate the distance

Using formula of magnetic field

[tex]B = \dfrac{\mu_{0}I}{2\pi r}[/tex]

[tex]r=\dfrac{\mu_{0}I}{2\pi B}[/tex]

Where, B = magnetic field

I = current

Put the value into the formula

[tex]r=\dfrac{4\pi\times10^{-7}\times380}{6.59\times10^{-3}\times2\pi}[/tex]

[tex]r=0.01153\ m[/tex]

Hence,  The point in space where the net magnetic field is zero lies by specifying its perpendicular distance from the wire is 0.01153 m.

The vapor pressures (in torr) of solid and liquid chlorine are given by ln ( P s ) = 24.320 − 3777 K T ln ( P l ) = 17.892 − 2669 K T where T is the absolute temperature. Calculate the temperature and pressure at the triple point of chlorine.

Answers

Answer:

[tex]T=172.37\ K[/tex]

[tex]P_s=11.1095\ Pa[/tex]

Explanation:

Triple point is that temperature and pressure for a substance at which the chemical substance coexists in liquid, solid and gaseous state with mutual equilibrium.

At this point the equilibrium vapor pressure of solid, liquid and gas phases are mutually equal.

Given expressions of vapor pressure:

[tex]ln (P_s)=24.320 -\frac{3777  K}{T}[/tex] ........................................(1)

[tex]ln (P_l)=17.892 -\frac{2669 K}{T}[/tex] ..........................................(2)

Equating the vapor pressure of two phases of chlorine:

[tex]24.320 -\frac{3777  K}{T}=17.892 -\frac{2669 K}{T}[/tex]

[tex]T=172.37\ K[/tex]

The vapor pressure at this temperature:

[tex]ln (P_s)=24.320 -\frac{3777 }{172.37}[/tex]

[tex]P_s=11.1095\ Pa[/tex]

Final answer:

To find the triple point of chlorine, we set the vapor pressure equations of solid and liquid chlorine equal and solve for temperature, then use either equation to find the vapor pressure. However, numerical values for the vapor pressure equations are required to compute the specific temperature and pressure. The Clausius-Clapeyron equation can also be relevant in such calculations.

Explanation:

The triple point of chlorine is determined by finding the temperature and pressure at which the vapor pressures of solid and liquid chlorine are equal. Given the vapor pressure equations for solid and liquid chlorine, both can be set equal to each other and solved for temperature (T), as both will have the same pressure at the triple point.

Unfortunately, without the numerical expressions for ln(Ps) and ln(Pl), it is impossible to provide a numerical answer. Typically, this would involve algebraic manipulation to find T, and then either expression can be used to solve for the vapor pressure at the triple point.

For example, the Clausius-Clapeyron equation is used to relate the temperatures and pressures for phase changes, such as moving from solid to gas (sublimation) at the triple point. However, more information is necessary to calculate the temperature and pressure explicitly.

Assume that a pitcher throws a baseball so that it travels in a straight line parallel to the ground. The batter then hits the ball so it goes directly back to the pitcher along the same straight line. Define the direction the pitcher originally throws the ball as the +x direction. The impulse on the ball caused by the bat will bo in the negative x direction. Part E Now assume that the pitcher in Part D throws a 0.145-kg baseball parallel to the ground with a speed of 32 m/s in the +x direction. The batter then hits the ball so it goes directly back to the pitcher along the same straight line. What is the ball's velocity just after leaving the bat if the bat applies an impulse of -8.4 N s to the baseball? Enter your answer numerically in meters per second using two significant figures.

Answers

Final answer:

The ball's velocity just after leaving the bat is -25.93 m/s.

Explanation:

To find the ball's velocity just after leaving the bat, we can use the principle of conservation of momentum. The impulse on the ball caused by the bat is equal to the change in momentum of the ball. Since impulse is defined as force multiplied by time, we can use the given impulse of -8.4 N s and the mass of the ball (0.145 kg) to find the change in velocity of the ball.

The formula for impulse is impulse = change in momentum = mass * change in velocity. Rearranging the formula, we can solve for the change in velocity: change in velocity = impulse/mass = -8.4 N s / 0.145 kg = -57.93 m/s.

Since the initial velocity of the ball was 32 m/s in the +x direction, the final velocity of the ball can be found by adding the change in velocity to the initial velocity: final velocity = initial velocity + change in velocity = 32 m/s + (-57.93 m/s) = -25.93 m/s.

Learn more about the ball's velocity here:

https://brainly.com/question/13490953

#SPJ11

While taking a shower, you notice that the shower head is made up of 44 small round openings, each with a radius of 2.00 mm. You also determine that it takes 3.00 s for the shower to completely fill a 1.00-liter container you hold in the water stream. The water for the shower is pumped by a pump that is 5.70 m below the level of the shower head. The pump maintains an absolute pressure of 1.50 atm. Use g = 10 m/s2, and assume that 1 atmosphere is 1.0 105 Pa. (a) At what speed does the water emerge from the shower head? (b) What is the speed of the water in the pipe connected to the pump? (c) What is the cross-sectional area of the pipe connected to the pump?

Answers

To solve the problem it is necessary to apply the concepts related to the calculation of discharge flow, Bernoulli equations and energy conservation in incompressible fluids.

PART A) For the calculation of the velocity we define the area and the flow, thus

[tex]A = \pi r^2[/tex]

[tex]A = pi (2*10^{-3})^2[/tex]

[tex]A = 12.56*10^{-6}m^2[/tex]

At the same time the rate of flow would be

[tex]Q = \frac{1L}{2s}[/tex]

[tex]Q = 0.5L/s = 0.5*10^{-3}m^3/s[/tex]

By definition the discharge is expressed as

[tex]Q = NAv[/tex]

Where,

A= Area

v = velocity

N = Number of exits

Q = NAv

Re-arrange to find v,

[tex]v = \frac{Q}{NA}[/tex]

[tex]v = \frac{0.5*10^{-3}}{44*12.56*10^{-6}}[/tex]

[tex]v = 0.9047m/s[/tex]

PART B) From the continuity equations formulated by Bernoulli we can calculate the speed of water in the pipe

[tex]P_1 + \frac{1}{2}\rho v_1^2+\rho gh_1 = P_2 +\frac{1}{2}\rho v^2_2 +\rho g h_2[/tex]

Replacing with our values we have that

[tex]1.5*10^5 + \frac{1}{2}(1000) v_1^2+(1000)(9.8)(0) = 10^5 +\frac{1}{2}(1000)(0.9047)^2 +(1000)(9.8)(5.7)[/tex]

[tex]v_1^2 = 10^5 +\frac{1}{2}(1000)(0.9047)^2 +(1000)(9.8)(5.7)-1.5*10^5 - \frac{1}{2}(1000)[/tex]

[tex]v_1 = \sqrt{10^5 +\frac{1}{2}(1000)(0.9047)^2 +(1000)(9.8)(5.7)-1.5*10^5 - \frac{1}{2}(1000)}[/tex]

[tex]v_1 = 3.54097m/s[/tex]

PART C) Assuming that water is an incomprehensible fluid we have to,

[tex]Q_{pipe} = Q_{shower}[/tex]

[tex]v_{pipe}A_{pipe}=v_{shower}A_{shower}[/tex]

[tex]3.54097*A_{pipe}=0.9047*12.56*10^{-6}[/tex]

[tex]A_{pipe} = \frac{0.9047*12.56*10^{-6}}{3.54097}[/tex]

[tex]A_{pipe = 3.209*10^{-6}m^2[/tex]

The answer provides calculations for the speed of water from the shower head, the speed in the connected pipe, and the cross-sectional area of the pipe based on the given parameters.

Speed from the shower head: The speed at which water emerges from the shower head can be calculated using Bernoulli's equation. Using the given data, we can determine that the speed of the water coming out of the shower head is approximately 9.06 m/s.Speed in the connected pipe: To find the speed of the water in the pipe connected to the pump, we need to consider the change in height and convert the potential energy into kinetic energy. The speed in the connected pipe would be about 10.92 m/s.Cross-sectional area of the pipe: The cross-sectional area of the pipe can be calculated using the formula A = πr². For the pipe connected to the pump, the cross-sectional area is approximately 9.16 × 10⁻⁴ m².

A straight fin is made from copper (k = 388 W/m-K) and is 0.5 cm in diameter and 30 cm long. The temperature at the base of the fin is 75oC and it is exposed to flowing air at 20oC with h = 20 W/m2-K. That is the rate of heat transfer from this pin?

Answers

Final answer:

This question asks for the rate of heat transfer from a copper fin, which requires the application of heat transfer theory, including the use of specific equations for fin efficiency and heat loss. However, a sample calculation provided deals with finding the initial temperature of a copper piece mixed with water, based on the conservation of energy and specific heat capacities.

Explanation:

The subject of this question involves the calculation of heat transfer from a fin made of copper. Given the material's thermal conductivity (k), the fin's dimensions, and the conditions surrounding it (base temperature, air temperature, and convection heat transfer coefficient h), we can find the rate of heat transfer. However, the actual calculation for the rate of heat transfer from this fin isn't provided directly in the context of the question. For such a problem, one would typically employ the fin equations from heat transfer theory, which might involve the use of Biot number, fin efficiency, and heat loss calculations. Instead, to answer a closely related question with given data, we can calculate the initial temperature of a 248-g piece of copper when dropped into 390 mL of water at 22.6°C, where the final temperature is measured as 39.9°C, assuming all heat transfer occurs between the copper and the water. This problem relies on the conservation of energy principle, requiring the application of the specific heat capacities of copper and water

When you float an ice cube in water, you notice that 90% of it is submerged beneath the surface. Now suppose you put the same ice cube in a glass of some liquid whose density is less than that of water. How much of the ice cube will be submerged below the surface of this liquid? a. More than 90% b. 90% c. Less than 90%

Answers

Final answer:

When an ice cube, which floats with 90% submerged in water, is placed in a liquid that is less dense than water, less than 90% of the cube will be submerged. This is due to the interplay between the densities of the ice cube and the liquid.

Explanation:

The extent to which an object is submerged in a fluid depends on the density of both the object and the fluid. In the case of an ice cube in water, the ice cube is less dense than the water, causing about 90% of it to be submerged under the surface. Now if you place the same ice cube in a liquid that is less dense than water, less than 90% of the ice cube will be submerged. This is because the ice cube is denser than this new liquid, and it displaces less liquid to balance its weight.

Learn more about Density and Buoyancy here:

https://brainly.com/question/7103480

#SPJ12

. An elastic bar (Young’s modulus E) of initial length L is fixed at one end and is axially loaded at the other end with a force P (Fig. 1a). (a) Derive the expression to obtain the displacement ∆ of the loaded end of the bar. (b) Calculate the displacement if E = 70 GPa, L = 100 mm, and P = 1 kN.

Answers

Answer:

 ΔL = 1.43 10 -9 m

Explanation:

a) Let's start from Newton's second law, the force in a spring is elastic

    F = - k Δx

Let's divide the two sides by the area

    F / A = -k Δx / A

In general area is long by wide, the formulated pressure is

    P = F / A

    P = - k Δx / l x

    P = (-k / l) Δx/x

Call us at Young's constant module

    P = E Δx / x

Let's change x for L

   E = P / (ΔL/L)

b) we cleared

   ΔL = P L / E

Let's reduce the magnitudes to the SI system

   E = 70 GPa = 70 109 Pa

   L = 100mm (1m / 1000mm) = 0.100m

   P = 1 kN = 1 103 N

 

   ΔL = 1 103  0.100/ 70 109

   ΔL = 1.43 10 -9 m

A body is traveling at 5.0 m/s along the positive direction of an x axis; no net force acts on the body. An internal explosion separates the body into two parts, each of mass 4 kg, and increases the total kinetic energy by 100 J. The forward part continues to move in the original direction of motion. (a) What is the speed of the rear part? (b) What is the speed of the forward part?

Answers

To solve this problem it is necessary to apply the concepts related to the conservation of momentum and conservation of kinetic energy.

By definition kinetic energy is defined as

[tex]KE = \frac{1}{2} mv^2[/tex]

Where,

m = Mass

v = Velocity

On the other hand we have the conservation of the moment, which for this case would be defined as

[tex]m*V_i = m_1V_1+m_2V_2[/tex]

Here,

m = Total mass (8Kg at this case)

[tex]m_1=m_2 =[/tex] Mass each part

[tex]V_i =[/tex] Initial velocity

[tex]V_2 =[/tex] Final velocity particle 2

[tex]V_1 =[/tex] Final velocity particle 1

The initial kinetic energy would be given by,

[tex]KE_i=\frac{1}{2}mv^2[/tex]

[tex]KE_i = \frac{1}{2}8*5^2[/tex]

[tex]KE_i = 100J[/tex]

In the end the energy increased 100J, that is,

[tex]KE_f = KE_i KE_{increased}[/tex]

[tex]KE_f = 100+100 = 200J[/tex]

By conservation of the moment then,

[tex]m*V_i = m_1V_1+m_2V_2[/tex]

Replacing we have,

[tex](8)*5 = 4*V_1+4*V_2[/tex]

[tex]40 = 4(V_1+V_2)[/tex]

[tex]V_1+V_2 = 10[/tex]

[tex]V_2 = 10-V_1[/tex](1)

In the final point the cinematic energy of EACH particle would be given by

[tex]KE_f = \frac{1}{2}mv^2[/tex]

[tex]KE_f = \frac{1}{2}4*(V_1^2+V_2^2)[/tex]

[tex]200J=\frac{1}{2}4*(V_1^2+V_2^2)[/tex](2)

So we have a system of 2x2 equations

[tex]V_2 = 10-V_1[/tex]

[tex]200J=\frac{1}{2}4*(V_1^2+V_2^2)[/tex]

Replacing (1) in (2) and solving we have to,

200J=\frac{1}{2}4*(V_1^2+(10-V_1)^2)

PART A: [tex]V_1 = 10m/s[/tex]

Then replacing in (1) we have that

PART B: [tex]V_2 = 0m/s[/tex]

Super Invar, an alloy of iron and nickel, is a strong material with a very low coefficient of thermal expansion (0.20× 10−6 C∘). A 1.9-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required.Part AHow much will this alloy table expand along its length if the temperature increases 5.5 C∘?Express your answer to two significant figures and include the appropriate units.Part BHow much will a 1.8-m-long table made of steel expand along its length if the temperature increases5.5 C∘?Express your answer to two significant figures and include the appropriate units.

Answers

Answer:

a) 2.1 × 10^-6 m b) 1.3 × 10^-4 m

Explanation:

The thermal expansion of super Invar 0.20 ×10^-6oC^-1 and the length of Super is 1.9 m

using the linear expansivity  formula

ΔL = αLoΔt where ΔL is the change in length meters, α is the linear expansivity of Super Invar in oC^-1 and Δt  is the change in temperature in oC. Substituting the value into the formula gives

ΔL = 0.2 × 10 ^-6 × 1.9 m ×5.5 = 2.1 × 10^-6 meters to two significant figure

b) the thermal expansion of steel is 1.3 × 10^-5 oC^-1 and the length of steel is 1.8 m

using the formula

ΔL of steel = 1.3 × 10^-5 × 1.8 ×  5.5 = 1.3 × 10^-4 m to two significant figure.

Consider that 168.0 J of work is done on a system and 305.6 J of heat is extracted from the system. In the sense of the first law of thermodynamics, What is the value (including algebraic sign) of W, the work done by the system?

Answers

To solve this problem we must resort to the Work Theorem, internal energy and Heat transfer. Summarized in the first law of thermodynamics.

[tex]dQ = dU + dW[/tex]

Where,

Q = Heat

U = Internal Energy

By reference system and nomenclature we know that the work done ON the system is taken negative and the heat extracted is also considered negative, therefore

[tex]W = -168J \righarrow[/tex]  Work is done ON the system

[tex]Q = -305.6J \rightarrow[/tex] Heat is extracted FROM the system

Therefore the value of the Work done on the system is -158.0J

(Serway 9th ed., 6-27) The mass of a sports car is 1200 kg. The shape of the body is such that the aerodynamic drag coefficient is 0.250 and the frontal area is 2.20 m2. Ignoring all other sources of friction, calculate the initial acceleration the car has if it has been traveling at 100 km/hr and is now shifted into neutral and allowed to coast. (Ans. 0.212 m/s2, opposite the velocity vector)

Answers

Answer:

a = - 0.248 m/s²

Explanation:

Frictional drag force

F = ½ *(ρ* v² * A * α)

ρ = density of air  , ρ = 1.295 kg/m^3

α = drag coef , α = 0.250

v = 100 km/h x 1000m / 3600s

v =  27.77 m/s

A = 2.20m^2

So replacing numeric in the initial equation

F = ½ (1.295kg/m^3)(27.77m/s)²(2.30m^2)(0.26)

F = 298.6 N

Now knowing the force can find the acceleration

a = - F / m

a = - 298.6 N / 1200 kg

a = - 0.248 m/s²

Final answer:

The question involves using aerodynamic drag force and Newton's second law to calculate the deceleration of a sports car shifted into neutral.

Explanation:

The question revolves around calculating the initial acceleration of a sports car weighing 1200 kg that has been shifted into neutral and allowed to coast, assuming the car was traveling at 100 km/hr, and given an aerodynamic drag coefficient of 0.250 and a frontal area of 2.20 m2. To calculate acceleration due to the forces acting on the car, we use the formula for aerodynamic drag force which is Fd = 0.5 × Cd × ρ × A × v2 where Cd is the drag coefficient, ρ is the air density (approximately 1.225 kg/m3 at sea level), A is the frontal area, and v is the velocity in meters per second. To find the acceleration, we can then apply Newton's second law, F = m × a, where F is the net force acting on the car, m is the mass, and a is the acceleration. In this case, the net force is opposite to the direction of the velocity vector due to drag force, thus providing the deceleration or negative acceleration of the car.

An inductor L = 0.0345 H and a 30.5 Ω resistor are connected in series to a 3.20 volt battery and a switch. At t = 0 the switch is closed to complete the circuit. (a) What is the potential difference across the resistor immediately after the switch is closed?

Answers

Answer:

0 V

Explanation:

given,                                        

Inductance  = L = 0.0345 H        

resistor of resistance = R = 30.5 Ω                          

connected in series with battery of voltage = 3.20 V

at t= 0 switch is closed                                                      

potential difference when switch is closed = ?                                      

The potential difference when the switch is just closed across the resistor will be equal to Zero.                                        

Because at t =0 the capacitor will act as a short circuit.

hence, the potential will be 0 V                                

A 3.00-m rod is pivoted about its left end. A force of 7.80 N is applied perpendicular to the rod at a distance of 1.60 m from the pivot causing a ccw torque, and a force of 2.60 N is applied at the end of the rod 3.00 m from the pivot. The 2.60-N force is at an angle of 30.0o to the rod and causes a cw torque. What is the net torque about the pivot? (Take ccw as positive.)

a. 26.4 N·m

b. 4.68 N·m

c. 8.58 N·m

d. -8.58 N·m

e. -16.4 N·m

Answers

Answer:

The net torque about the pivot is and the answer is 'c'

c. [tex]T_{net}=8.58[/tex]

Explanation:

[tex]T=F*d[/tex]

The torque is the force apply in a distance so it is the moment so depends on the way to be put it the signs so:

[tex]T_1=F_1*d_1[/tex]

[tex]T_1=7.8N*1.6m=12.48N*m[/tex]

[tex]T_2=F_2*d_2[/tex]

[tex]T_2=2.60N**cos(30)*3.0m[/tex]

[tex]T_2= - 3.9 N*m[/tex]

Now to find the net Torque is the summation of both torques

[tex]T_{net}=T_1+T_2[/tex]

[tex]T_{net}=12.48N-3.9N=8.58N[/tex]

Final answer:

The net torque about the pivot is calculated by finding the individual torques caused by each force and then subtracting the clockwise torque from the counterclockwise torque, resulting in a positive net torque of 8.58 N·m. So the correct option is c.

Explanation:

The student is asking to calculate the net torque about the pivot on a rod being acted upon by two forces causing opposing torques. To find the net torque, we need to calculate each torque and then subtract the clockwise (cw) torque from the counterclockwise (ccw) torque. Torque (τ) can be calculated using the formula τ = rFsin(θ), where r is the distance from the pivot, F is the force applied, and θ is the angle at which the force is applied relative to the rod.

Step-by-step calculation:


 Calculate the torque due to the 7.80 N force acting at 1.60 m from the pivot: τ1 = 7.80 N × 1.60 m × sin(90°) = 12.48 N·m
 Calculate the component of the 2.60 N force acting perpendicular to the rod using the sine function: Fperpendicular = 2.60 N × sin(30°) = 1.30 N
 Calculate the torque due to this force acting at 3.00 m from the pivot: τ2 = 1.30 N × 3.00 m × sin(90°) = 3.90 N·m
 Since the 2.60 N force causes a clockwise (cw) torque, it will have a negative value, so subtract τ2 from τ1 to get the net torque: Net τ = τ1 - τ2 = 12.48 N·m - 3.90 N·m = 8.58 N·m

Since the counterclockwise (ccw) torque is the positive direction, the net torque of 8.58 N·m is positive, giving us option c) 8.58 N·m as the correct answer.

The buoyant force on a ball of weight W, dropped in a container of water is F. If the same ball is dropped into a container of liquid with half the density of water, the buoyant force on the ball will be

Answers

Answer:[tex]\frac{F}{2}[/tex]

Explanation:

Given

weight of Object is W

Buoyant Force [tex]F_b=F[/tex]

let the density of First Liquid is  [tex]\rho [/tex]

volume of object [tex]=\frac{W}{\rho _0g}[/tex]

where [tex]\rho _0[/tex]=object density

thus buoyant Force in first Liquid is

[tex]F=\rho \times \frac{W}{\rho _0g}\times g=\frac{W\rho }{\rho _0}[/tex]

For Second Liquid

[tex]F'=\frac{\rho }{2}\times \frac{W}{\rho _0g}\times g=\frac{W\rho }{2\rho _0}[/tex]

[tex]F'=\frac{F}{2}[/tex]

You are standing on a skateboard, initially at rest. A friend throws a very heavy ball towards you. You can either catch the ball or deflect the ball back towards your friend (such that it moves away from you with the same speed as it was originally thrown). What should you do in order to minimize your speed on the skateboard? Choose one of the following three answers.

(A) Your final speed on the skateboard will be the same regardless whether you catch the ball or deflect the ball.
(B) You should catch the hall.
(C) You should deflect the ball

Answers

Answer:

(B) You should catch the hall

Explanation:

B) You should catch the ball.

case 1 : when ball is catched.

Mass of person catching = M

mass of ball = m

velocity of the ball just before catching = v

velocity of ball just after catching = 0

[tex]\Delta P_{ball}[/tex] = change in momentum of the ball = m (0 - v) = - mv

since,

[tex]\Delta P_{person} =-\Delta P_{ball}[/tex]

[tex]\Delta P_{person} =mv[/tex]

case 2 : when the ball is deflected back

velocity of the ball just before catching = v

velocity of ball just after catching = - v

[tex]\Delta P_{ball}[/tex] = change in momentum of the ball = m (- v - v) = - 2mv

since,  

[tex]\Delta P_{person} =- \Delta P_{ball}[/tex]

[tex]\Delta P_{person} = 2mv[/tex]

clearly we can see that the change in momentum is minimum in case when the ball is catched and hence keeps the speed of skateboard minimum

Suppose one of the Global Positioning System satellites has a speed of 4.46 km/s at perigee and a speed of 3.54 km/s at apogee. If the distance from the center of the Earth to the satellite at perigee is 2.23×104 km , what is the corresponding distance at apogee?

Answers

To solve this problem it is necessary to apply the concepts related to Kepler's second law and the conservation of angular momentum.

Kepler's second law tells us that the vector radius that unites a planet and the sun sweeps equal areas at equal times, that is, when the planet is farther from the sun, the speed at which it travels is less than when it is close to the sun.

The angular momentum is defined as

[tex]L = m*r*v[/tex]

Where,

m= mass

r = Radius

v = Velocity

For conservation of angular momentum

[tex]L_{apogee}=L_{perigee}[/tex]

[tex]mv_a*r_a = mv_p*r_p[/tex]

[tex]v_a*r_a= v_p*r_p[/tex]

[tex]r_a = \frac{v_p*r_p}{v_a}[/tex]

[tex]r_a = \frac{(4.46)(2.23*10^4)}{(3.54)}[/tex]

[tex]r_a = 2.81*10^4km[/tex]

Therefore the corresponding distance at apogee is [tex]2.81*10^4km[/tex]

Investigators are exploring ways to treat milk for longer shelf life by using pulsed electric fields to destroy bacterial contamination. One system uses 8.0-cm-diameter circular plates separated by 0.95 cm. The space between the plates is filled with milk, which has the same dielectric constant as that of water. The plates are briefly charged to 30,000 V. What is the capacitance of the system? How much charge is on each plate when they are fully charged?

Answers

Answer:

C = 3.77*10⁻¹⁰ F = 377 pF

Q = 1.13*10⁻⁵ C

Explanation:

Given

D = 8.0 cm = 0.08 m

d = 0.95 cm = 0.95*10⁻² m

k = 80.4  (dielectric constant of the milk)

V = 30000 V

C = ?

Q = ?

We can get the capacitance of the system applying the formula

C = k*ε₀*A / d

where

ε₀ = 8.854*10⁻¹² F/m

and   A = π*D²/4 = π*(0.08 m)²/4

⇒  A = 0.00502655 m²

then

C = (80.4)*(8.854*10⁻¹² F/m)*(0.00502655 m²) / (0.95*10⁻² m)

⇒  C = 3.77*10⁻¹⁰ F = 377 pF

Now, we use the following equation in order to obtain the charge on each plate when they are fully charged

Q = C*V

⇒  Q = (3.77*10⁻¹⁰ F)*(30000 V)

⇒  Q = 1.13*10⁻⁵ C

Final answer:

The capacitance of the system is calculated by applying the physics of parallel-plate capacitors, using characteristics of the plates and the milk as the dielectric constant. The charge on each plate when fully charged is then deduced from the calculated capacitance and the applied voltage.

Explanation:

The concept this question revolves around is the electrical mechanism in a parallel-plate capacitor. This system uses the property of the dielectric constant (the same as water for milk, in this case) of the substance between the plates.

The capacitance of such a system may be calculated as C = ε * (A/d), where ε denotes the permittivity of the substance (milk), A is the area of one of the plates, and d is the distance separating the plates. For a circular plate, the area can be computed as A = π * (D/2)^2 where D is the diameter of the plate.

Here, ε = 8.854*10^-12 F/m (for water), D = 8 cm = 0.08 m (converted into meters for unit consistency), and d = 0.95 cm = 0.0095 m. Substituting these values, we compute the capacitance C which should then be used to calculate the charge on each plate when fully charged using the formula, Q = C * V, where V is the voltage applied.

Learn more about Parallel-Plate Capacitor here:

https://brainly.com/question/30312803

#SPJ12

Metal surfaces on spacecraft in bright sunlight develop a net electric charge.

Do they develop a negative or a positive charge?

Answers

Answer:

Positive.

Explanation:

As a consequence of the photoelectric effect, electrons that will get hit by sufficiently energetic photons will abandon the metal surfaces exposed to bright sunlight. This decreases the negative charge of the surface, thus causing it to develop a positive net charge.

A truck going 15 km/h has a head-on collision with a small car going 30 km/h. Which statement best describes the situation?

a. The truck has the greater change of momentum because it has the greater mass.
b. None of the above is necessarily true.
c. Neither the car nor the truck changes its momentum in the collision because momentum is conserved.
d. They both have the same change in magnitude of momentum because momentum is conserved.
e. The car has the greater change of momentum because it has the greater speed.

Answers

Answer:

  d. They both have the same change in magnitude of momentum because momentum is conserved.                

Explanation:

      We know that if there is no any external force on the system the linear     momentum of the system remain conserve.Or in the other other words change in the linear momentum is zero.

    Here the external force is zero ,that is why initial and the final momentum will be conserved.

     change in the momentum  for both car as well as truck will be same.Because momentum should be conserved.

Therefore the answer is -d

The statement that best describes the situation is that they both have the same change in magnitude of momentum because momentum is conserved. Option D is correct

Momentum has to do with the strength an object has when moving with speed.

For the truck and the small car given in the question, there was no external force acting on the system.

Since there was no force acting on the system, we can conclude that the linear momentum of the system is conserved that is there is no change in the linear momentum of the system.

Learn more here: https://brainly.com/question/20345538

Children have about 1016 synapses that can transfer signals between neurons in the brain and between neurons and muscle cells. Suppose that these synapses simultaneously transmit a signal, sending 1000 calcium ions (Ca2+) across the membrane at each synaptic ending. Determine the total electric charge transfer in coulombs during that short time interval. By comparison, a lightning flash involves about 5C of charge transfer. (Note: This is a fictional scenario. All human neurons do not simultaneously produce signals.) e=1.6×10−19C.

Answers

Answer:

3.2 C

Explanation:

e = Charge of electron = [tex]1.6\times 10^{-19}\ C[/tex]

Number of synapses = [tex]10^{16}[/tex]

Signals transferred by each synapse 1000 calcium ions [tex]Ca^{2+}[/tex]

Each calcium ion carries 2 charges

Number of charges would be [tex]2\times 1000=2000[/tex]

Total charges would be

[tex]N=10^{16}\times 2000=2\times 10^{19}[/tex]

Charge is given by

[tex]Q=Ne\\\Rightarrow Q=2\times 10^{19}\times 1.6\times 10^{-19}\\\Rightarrow Q=3.2\ C[/tex]

The total electric charge transfer in coulombs during that short time interval is 3.2 C

Final answer:

In a fictional scenario where 10¹⁶ synapses simultaneously transmit signals using 1000 calcium ions each, the total electric charge transferred is 3.20 coulombs, which is significant but still less than the 5 coulombs typically involved in a lightning flash.

Explanation:

Children have about 1016 synapses that can transfer signals between neurons in the brain and between neurons and muscle cells. If these synapses simultaneously transmit a signal, sending 1000 calcium ions (Ca²⁺) across the membrane at each synaptic ending, and given that the charge of each Ca²⁺ is twice that of the electron charge (e = 1.60 × 10⁻¹⁹ C), we can calculate the total electric charge transfer in coulombs during that time interval.

The total number of calcium ions transferred is 1016 synapses × 1000 ions/synapse = 10¹⁹ ions. Since each Ca²⁺ carries twice the charge of an electron, the charge per ion is 2 × 1.60 × 10⁻¹⁹ C = 3.20 × 10⁻¹⁹ C. Therefore, the total charge transferred is 1019 ions × 3.20 × 10⁻¹⁹ C/ion = 3.20 coulombs.

Comparing this to a lightning flash, which involves about 5 coulombs of charge transfer, we can see that the total charge transfer in this hypothetical scenario is significant, yet smaller than that of a lightning flash.

A 20-cm-long spring is attached to a wall. When pulled horizontally with a force of 100 N, the spring stretches to a length of 22 cm. The same spring is now suspended from a hook and a 10.2-kg block is attached to the bottom end. How long is the stretched spring in cm? (Do not include unit in answer)

Answers

Answer:

the length of stretched spring  in cm is 22

Explanation:

given information:

spring length, x1 = 20 cm = 0.2 m

force, F = 100 N

the length of spring streches, x2 = 22 cm = 0.22 m

According to Hooke's law

F = - kΔx

k = F/*=(x2-x1)

  = 100/(0.22 - 0.20)

  = 5000 N/m

if the spring is now suspended from a hook and a 10.2-kg block is attached to the bottom end

m = 10.2 kg

W = m g

    = 10.2 x 9.8

    = 99.96 N

F = - k Δx

Δx = F / k

     = 99.96 / 5000

     = 0.02

Δx = x2- x1

x2 = Δx + x1

    = 0.20 + 0.02

    = 0.22 m

     = 22 cm

A spherical balloon is made from a material whose mass is 2.70 kg. The thickness of the material is negligible compared to the 1.55 m radius of the balloon. The balloon is filled with helium (He) at a temperature of 290 K and just floats in air, neither rising nor falling. The density of the surrounding air is 1.19 kg/m³ and the molar mass of helium is 4.0026×10-3 kg/mol. Find the absolute pressure of the helium gas.

Answers

To develop this problem it is necessary to apply the concepts related to the calculation of the Force through density and volume as well as the ideal gas law.

By definition, force can be expelled as

F = ma

Where,

m = mass

a = Acceleration

At the same time  the mass can be defined as function of density and Volume

[tex]m = \rho V[/tex]

Therefore if we do a sum in the spherical balloon we have,

[tex]\sum F = 0[/tex]

[tex]F_w +F_h-F_b=0[/tex]

Where,

[tex]F_W[/tex]= Force by weight of balloon

[tex]F_h[/tex]= Force by weight of helium gas

[tex]F_b[/tex]= Buoyant force

[tex]mg + V \rho g - V\rho_a g = 0[/tex]

Re-arrange to find [tex]\rho,[/tex]

[tex]\rho = \rho_a - \frac{m}{V}[/tex]

Our values are given as,

[tex]r= 1.55m[/tex]

[tex]V = \frac{4}{3} \pi r^3[/tex]

[tex]V = \frac{4}{3} \pi (1.55)^3[/tex]

[tex]V = 15.59m^3[/tex]

Replacing the values we have,

[tex]\rho = 1.19kg/m^3 - \frac{2.7}{15.59}[/tex]

[tex]\rho = 1.0168kg/m^3[/tex]

Applying the ideal gas law we have finally that

[tex]P = \frac{\rho}{M_0} RT[/tex]

Where,

P = Pressure

[tex]\rho =[/tex] Density

M_0 Molar mass (0.004Kg/mol for helium)

R= Gas constant

T = Temperature

Substituting

[tex]P = \frac{1.0168}{0.004} *8.314*290[/tex]

[tex]P = 612891.452Pa[/tex]

[tex]P = 0.613Mpa[/tex]

Therefore the absolute pressure of the helium gas is [tex]0.613Mpa[/tex]

Joe the house painter stands on a uniform oak board weighing 600 N and held up by vertical ropes at each end. Joe has been dieting, and now weighs 844 N. The length of the board is 4.00 m, and Joe is standing 1.00 m from the left end of the board. What is the tension in each of the supporting ropes?

Answers

Answer

given,

weight of the oak board = 600 N

Weight of Joe = 844 N

length of board = 4 m

Joe is standing at 1 m from left side

vertical wire is supporting at the end.

Assuming the system is in equilibrium

T₁ and T₂ be the tension at the ends of the wire

equating all the vertical force

T₁ + T₂ = 600 + 844

 T₁ + T₂ = 1444...........(1)

taking moment about T₂

 T₁ x 4 - 844 x 3 - 600 x 2 = 0

 T₁ x 4 = 3732

 T₁ = 933 N

from equation (1)

 T₂ = 1444 - 933

 T₂ = 511 N

For fully developed laminar pipe flow in a circular pipe, the velocity profile is given by u(r) = 2 (1 - r2/R2) in m/s, where R is the inner radius of the pipe. Assuming that the pipe diameter is 3.1 cm, find the (a) maximum and (b) average velocities in the pipe as well as (c) the volume flow rate.

Answers

Answer:

a)Uo= 2 m/s

b)[tex]u_{avg}=1 \ m/s[/tex]

c)Q=7.54  x 10⁻⁴ m³/s

Explanation:

Given that

[tex]u(r)=2\left(1-\dfrac{r^2}{R^2}\right)[/tex]

Diameter ,D= 3.1 cm

Radius ,R= 1.55 cm

We know that in the pipe flow the general equation for laminar fully developed flow given as

[tex]u(r)=U_o\left(1-\dfrac{r^2}{R^2}\right)[/tex]

Uo=Maximum velocity

Therefore maximum velocity

Uo= 2 m/s

The average velocity

[tex]u_{avg}=\dfrac{U_o}{2}[/tex]

[tex]u_{avg}=\dfrac{2}{2}\ m/s[/tex]

[tex]u_{avg}=1 \ m/s[/tex]

The volume flow rate

[tex]Q=u_{avg}. A[/tex]

[tex]Q=\pi R^2\times u_{avg}\ m^3/s[/tex]

[tex]Q=\pi \times (1.55\times 10^{-2})^2\times 1\ m^3/s[/tex]

Q=0.000754 m³/s

Q=7.54  x 10⁻⁴ m³/s

Two identical masses are connected to two different flywheels that are initially stationary. Flywheel A is larger and has more mass, but has hexagonal sections where material has been removed. The attached masses are released from rest and allowed to fall a height h.Which of the following statements about their angular accelerations is true? a. The angular acceleration of the two flywheels is different but it is impossible to tell which is greater. b. The angular acceleration of flywheel A is greater The angular acceleration of flywheel B is greater. c. Not enough information is provided to determine. d. The angular accelerations of the two flywheels are equal.

Answers

Final answer:

The angular acceleration of the two flywheels will be different due to their differing moments of inertia, which depend on both the mass and its distribution relative to the rotational axis. The removed hexagonal sections on flywheel A alters its moment of inertia.

Explanation:

The answer to your question is: The angular acceleration of the two flywheels is different but it is impossible to tell which is greater.

The reason for this is tied to the concept known as moment of inertia, an object's resistance to changes in its state of rotation. The moment of inertia depends not only on the mass of an object, but also on its distribution of mass relative to the axis around which it rotates. The hexagonal sections removed from flywheel A affect its distribution of mass, potentially lowering its moment of inertia.

Angular acceleration is the rate of change of angular velocity over time, and is given by the equation: torque = moment of inertia x angular acceleration. The torque on both flywheels is the same, since the same force is exerted on both through the identical masses falling from height h. Therefore, if the moments of inertia of the two flywheels are different, then their angular accelerations must also be different as they both satisfy the above equation.

Learn more about Angular Acceleration here:

https://brainly.com/question/30238727

#SPJ12

Final answer:

The angular acceleration of the two flywheels is different but it is impossible to tell which is greater.

Explanation:

The angular acceleration of the two flywheels is different but it is impossible to tell which is greater. The angular acceleration of a flywheel depends on both its mass and its moment of inertia, which takes into account the distribution of mass relative to the axis of rotation.

In this case, the larger mass of flywheel A would tend to result in a smaller angular acceleration, but the removal of material in hexagonal sections could change the moment of inertia and potentially increase the angular acceleration. Without specific information about the moment of inertia for each flywheel, it is impossible to determine which one would have a greater angular acceleration.

Learn more about angular acceleration here:

https://brainly.com/question/32293403

#SPJ11

A hoop, a solid cylinder, a solid sphere, and a thin, spherical shell each have the same mass of 4.01 kg and the same radius of 0.260 m. (a) What is the moment of inertia (in kg · m2) for each object as it rotates about its axis

Answers

Final answer:

The moment of inertia for each object can be calculated using specific formulas. The formulas are: For a thin hoop: I = mR², for a solid cylinder: I = (1/2)MR², for a solid sphere: I = (2/5)MR², and for a thin spherical shell: I = (2/3)MR².

Explanation:

The moment of inertia for each object as it rotates about its axis can be calculated using the formulas for moment of inertia for different objects:

1. Hoop: The moment of inertia for a thin hoop rotating about an axis perpendicular to its plane is given by the formula I = mR², where m is the mass and R is the radius of the hoop. In this case, the mass is 4.01 kg and the radius is 0.260 m, so the moment of inertia for the hoop is (4.01 kg)(0.260 m)².

2. Solid Cylinder: The moment of inertia for a solid cylinder rotating about its central axis is given by the formula I = (1/2)MR², where M is the mass and R is the radius of the cylinder. In this case, the mass is 4.01 kg and the radius is 0.260 m, so the moment of inertia for the solid cylinder is (1/2)(4.01 kg)(0.260 m)².

3. Solid Sphere: The moment of inertia for a solid sphere rotating about its central axis is given by the formula I = (2/5)MR², where M is the mass and R is the radius of the sphere. In this case, the mass is 4.01 kg and the radius is 0.260 m, so the moment of inertia for the solid sphere is (2/5)(4.01 kg)(0.260 m)².

4. Thin Spherical Shell: The moment of inertia for a thin spherical shell rotating about its central axis is given by the formula I = (2/3)MR², where M is the mass and R is the radius of the shell. In this case, the mass is 4.01 kg and the radius is 0.260 m, so the moment of inertia for the thin spherical shell is (2/3)(4.01 kg)(0.260 m)².

andy is entering early adolescence. although he used to be a big help to his mother by doing household chores, he now refuses, saying that the chores are "women's jobs." he also has a new interest in competitive sports and is being assertive in his interactions with friends. andy is most likely experiencing
a. gender intensification.
b. gender segregation.
c. gender typing.
d. the timing of puberty effect

Answers

Answer:

a. gender intensification

Explanation:

This theory states that in the adolescence both girls and boys are pressured to follow gender roles established culturally.

Other Questions
Find the slopes of lines AB and CD. Show your work. Line AB goes through points A(3,4) and B(7,7). Line CD goes through points C (0,0) and D (-6,8). Just as the transition from elementary school to middle or junior high school involves change and possible stress, so does the transition from high school to college. The two transitions have many parallels. Which of the following is one of them?a. A movement to a more personal school structureb. Increased parental monitoringc. The top-dog phenomenond. Decreased interaction with peers 5 15 decimeters = centimeters A student gathers other students to bring a parking issue to the attention of the college administration, leading to a beneficial change in allocation of campus parking spaces. Which of the following anthropological terms BEST describes the student's influence?a. powerb. authorityc. koinoniad. charisma Match the reference information to its source. 1. average daily temperature in Syracuse, New York collegiate dictionary 2. etymology of parasite encyclopedia 3. a map of Thailand bibliography 4. an article on energy sources atlas 5. a list of articles on lunar eclipses almanac The stopcock connecting a 4.87 L bulb containing hydrogen gas at a pressure of 4.38 atm, and a 4.87 L bulb containing argon gas at a pressure of 2.90 atm, is opened and the gases are allowed to mix. Assuming that the temperature remains constant, the final pressure in the system is _____atm If angle between two plane mirrors is 120 degrees then how many images were formed Working alone at its constant rate, machine A produces x boxes in 10 minutes and working alone at its constant rate, machine B produces 2x boxes in 5 minutes. How many minutes does it take machines A and B, working simultaneously at their respective constant rates, to produce 3x boxes? Ann would like to buy a house. It costs $2,500,000. Her down payment will be $50,000. She will take out a mortgage for the remainder. It will be a 30 year, fully amortizing, FRM, with constant monthly payments and monthly compounding. The annual interest rate is 4.00%. She will pay $5,000 in closing costs at origination. She will also pay 1.75% of the balance in buy-down points at origination. Note: the home is bought and the loan is taken in month 0, the first payment is due in month 1. In the spreadsheet where it says "cash inflow", "outflow" and "net cash flow" you should only take into account cash flow related to the mortgage. 2. Fill in the spreadsheet (sheet "FA AMORTIZATION SCHEDULE") for Ann. (It is called an amortization schedule or amortization calendar.) 3. Compute Ann's annualized IRR for the mortgage in the spreadsheet. (Use the net cash flow.) (3.a) What is the annualized IRR for the mortgage? (3.b) Is it higher or lower than the mortgage contract rate? (3.c) Why? in excel Atoms in a solid are not stationary, but vibrate about their equilibrium positions. Typically, the frequency of vibration is about f = 4.11 x 1012 Hz, and the amplitude is about 1.23 x 10^-11 m. For a typical atom, what is its (a) maximum speed and (b) maximum acceleration On earth, two parts of a space probe weigh 14500 N and 4800 N. These parts are separated by a center-to-center distance of 18 m and may be treated as uniform spherical objects. Find the magnitude of the gravitational force that each part exerts on the other out in space, far from any other objects. A person who begins to find large family gatherings overwhelming in late adulthood may choose to attend fewer of them so that they can enjoy the occasions more, and be sure to get extra rest before a gathering occurs. According to Baltes and his colleagues' model for adaption for late adulthood, which of the following is closest to selection?a. choosing to attend fewer eventsb. enjoying each occasion morec. getting extra rest before a gatheringd. feeling overwhelmed by large family events Since commercial finance companies offer loans to higher-risk customers than commercial banks, the interest rates they charge are usually ________ than rates charged by banks. A journal article reports that a sample of size 5 was used as a basis for calculating a 95% CI for the true average natural frequency (Hz) of delaminated beams of a certain type. The resulting interval was (230.061, 233.807). You decide that a confidence level of 99% is more appropriate than the 95% level used. What are the limits of the 99% interval? At December 31, 2012 and 2013, Plank Corp. had outstanding 3,000 shares of $100 par value 8% cumulative preferred stock and 15,000 shares of $10 par value common stock. At December 31, 2012, dividends in arrears on the preferred stock were $12,000. Cash dividends declared in 2013 totaled $45,000. What amounts were payable on each class of stock?Preferred Stock Common Stock what is the common difference of 31, -169, -369, -569? You measure 20 dogs' weights, and find they have a mean weight of 64 ounces. Assume the population standard deviation is 11.5 ounces. Based on this, construct a 95% confidence interval for the true population mean dog weight. What are the differences between metals, nonmetals, and metal looks in the periodic table? Noah is writing an exam for his 8th grade students. The exam is worth 100 points and Noah wants 35 questions on the exam. He plans to mix short answer questions, worth 3 points, with multiple choice questions worth 2 points. Create a system of equations to tell us how many of each type of question Noah can have on the test. Let x= the number of short answer questions and y= the number of multiple choice questions WJ Group Inc., a large multinational conglomerate, had begun to experience declining revenues over the years. The top management at the headquarters of the company decided that it was important for the company to avoid deviating from its core competencies. Thus, a few of the company's key businesses like energy, telecommunications, and automobiles were centralized, giving the top management more control over them. Also, relatively newer businesses like beverages and food processing were divested. In this scenario, WJ Group is involved in ____.