The speed you compute by dividing your car's mileage by the time of travel is the ______ speed of the car, whereas the speed your speedometer reads is the car's ________speed.

Answers

Answer 1

Answer:

average and instant

Explanation:

The average speed is the ratio of the total path traveled and the time it took to travel that path, that is why the first space must be average speed, this because it takes into account the total amount of distance, and the total amount of time.

Instant speed, is the speed an objet (in this case a car) has in a particular moment in time, for this speed it doesn't matter the distance or the time that the car has traveled, it only matters the speed in that moment, that is what the speedometer measures, thus the second blank space must be instant speed.


Related Questions

Two identical conducting spheres, fixed in place, attract each other with an electrostatic force of 0.116 N when their center-to-center separation is 65.4 cm. The spheres are then connected by a thin conducting wire. When the wire is removed, the spheres repel each other with an electrostatic force of 0.0273 N. Of the initial charges on the spheres, with a positive net charge, what was (a) the negative charge on one of them and (b) the positive charge on the other? (Assume the negative charge has smaller magnitude.)

Answers

Answer:

Part a)

[tex]q_1 = -1.47 \times 10^{-6} C[/tex]

Part b)

[tex]q_2 = 3.75 \times 10^{-6} C[/tex]

Explanation:

Let the charge on two spheres is q1 and q2

now the force between two charges are

[tex]F = \frac{kq_1q_2}{r^2}[/tex]

[tex]0.116 = \frac{(9\times 10^9)(q_1)(q_2)}{0.654^2}[/tex]

[tex]q_1 q_2 = 5.51 \times 10^{-12}[/tex]

now when we connect then with conducting wire then both sphere will equally divide the charge

so we will have

[tex]q = \frac{q_1-q_2}{2}[/tex]

now we have

[tex]0.0273 = \frac{(9\times 10^9)(\frac{q_1- q_2}{2})^2}{0.654^2}[/tex]

[tex]q_1 - q_2 = 2.28\times 10^{-6} C[/tex]

now we will have

Now we can solve above two equations

Part a)

negative charge on the sphere is

[tex]q_1 = -1.47 \times 10^{-6} C[/tex]

Part b)

positive charge on the sphere is

[tex]q_2 = 3.75 \times 10^{-6} C[/tex]

Consider two displacements, one of magnitude 15 m and another of magnitude 20 m. What angle between the directions of this two displacements give a resultant displacement of magnitude (a) 35 m, (b) 5 m, and (c) 25 m.

Answers

Answer:

a) 0°

b) 180°

c) 90°

Explanation:

Hello!

To solve this question let a be the vector whose length is 15 m and b the vector of length 20 m

So:

|a | = 15

|b | = 20

Since we are looking for the angle between the vectors we need to calculate the length of the sum of the two vectors, this is:

[tex]|a+b|^{2} = |a|^{2} + |b|^{2} + 2 |a||b|cos(\theta)[/tex]

Now we replace the value of the lengths:

[tex]|a+b|^{2} = 15^{2} + 20^{2} + 2*15*20*cos(\theta)[/tex]

[tex]|a+b|^{2} = 625 + 600*cos(\theta)[/tex] --- (1)

Now, if:

a) |a+b| = 35

First we can see that 20 + 15 = 35, so the angle must be 0, lets check this:

[tex]35^{2} = 625 + 600*cos(\theta)[/tex]

[tex]1225 = 625 + 600*cos(\theta)[/tex]

[tex]600 =  600*cos(\theta)[/tex]

[tex]1= cos(\theta)[/tex]

and :

[tex]\theta = arccos(1)[/tex]

      θ = 0

b) |a+b|=5

From eq 1 we got:

[tex]\theta = arccos(\frac{|a+b|^{2}-625}{600})[/tex]   --- (2)

[tex]\theta = arccos(\frac{|a+b|^{2}-625}{600})[/tex]

[tex]\theta = arccos(-1)[/tex]

  θ = π     or    θ = 180°

c) |a+b|=25

[tex]\theta = arccos(\frac{|25|^{2}-625}{600})[/tex]

[tex]\theta = arccos(-1)[/tex]

  θ = π/2     or    θ = 90°

Final answer:

In vector addition, an angle of 0° between two vectors gives a resultant of 35 m, an angle of 180° gives a resultant of 5 m, and the angle for a resultant of 25 m can be found using the Law of Cosines.

Explanation:

The question involves the concept of vector addition and the use of trigonometry to determine the resultant displacement when two vectors are combined at various angles. The displacement vectors have magnitudes of 15 m and 20 m, and we are interested in finding the angles that would result in resultant displacements of 35 m, 5 m, and 25 m, respectively.

For (a) a resultant displacement of 35 m, the two vectors must be added in the same direction. This implies that the angle between them is 0°.

For (b) a resultant displacement of 5 m, the two vectors must be in exactly opposite directions. Since the difference in magnitudes is 5 m, this means that the larger vector (20 m) partially cancels out the smaller vector (15 m). Hence, the angle between them is 180°.

For (c) a resultant displacement of 25 m, we can use the Law of Cosines to determine the angle:

c2 = a2 + b2 - 2ab cos(θ)

Where a = 15 m, b = 20 m, and c = 25 m. Solving this equation will give us the value of θ.

A 0.010 kg ball is shot from theplunger of a pinball machine.
Because of a centripetal force of0.025 N, the ball follows a
circulararc whose radius is 0.29 m. What isthe speed of the
ball?

Answers

Answer:

v = 0.85 m/s

Explanation:

Given that,

Mass of the ball, m = 0.01 kg

Centripetal force on the ball, F = 0.025 N

Radius of the circular path, r = 0.29 m

Let v is the speed of the ball. The centripetal force of the ball is given by :

[tex]F=\dfrac{mv^2}{r}[/tex]

[tex]v=\sqrt{\dfrac{Fr}{m}}[/tex]

[tex]v=\sqrt{\dfrac{0.025\times 0.29}{0.01}}[/tex]

v = 0.85 m/s

So, the speed of the ball is 0.85 m/s. Hence, this is the required solution.

Three objects are dropped from the top of a building. The first is thrown straight down with a velocity v, the second is thrown straight up with a velocity 2v, and the third is simply dropped. Which one has the highest speed when it hits the ground?

Answers

Answer:

Second ball

Explanation:

When a ball is thrown up with a certain velocity when the object reaches the same point from where it was thrown the velocity of the object becomes equal to the velocity with which the ball was thrown.

First ball

[tex]v_g_1^2-u^2=2as\\\Rightarrow v_g_1=\sqrt{2as+u^2}\\\Rightarrow v_g_1=\sqrt{2as+v^2}[/tex]

Second ball

[tex]v_g_2^2-u^2=2as\\\Rightarrow v_g_2=\sqrt{2as+u^2}\\\Rightarrow v_g_2=\sqrt{2as+4v^2}[/tex]

Third ball

[tex]v_g_3^2-u^2=2as\\\Rightarrow v_g_3=\sqrt{2as+0^2}\\\Rightarrow v_g_3=\sqrt{2as}[/tex]

From the equations above it can be seen that the second ball will have the highest velocity when it hits the ground.

So, [tex]v_g_3<v_g_1<v_g_2[/tex]

There is a naturally occurring vertical electric field near the Earth’s surface that points toward the ground. In fair weather conditions, in an open field, the strength of this electric field is 95.0 N/C . A spherical pollen grain with a radius of 12.0 μm is released from its parent plant by a light breeze, giving it a net charge of −0.700 fC (where 1 fC=1×10−15 C ). What is the ratio of the magnitudes of the electric force to the gravitational force, ????electric/????grav , acting on the pollen? Pollen is primarily water, so assume that its volume mass density is 1000 kg/m3 , identical to the volume mass density of water.

Answers

Answer:

[tex]\frac{F}{W} = 9.37 \times 10^{-4}[/tex]

Explanation:

Radius of the pollen is given as

[tex]r = 12.0 \mu m[/tex]

Volume of the pollen is given as

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

[tex]V = \frac{4}{3}\pi (12\mu m)^3[/tex]

[tex]V = 7.24 \times 10^{-15} m^3[/tex]

mass of the pollen is given as

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

[tex]m = 7.24 \times 10^{-12}[/tex]

so weight of the pollen is given as

[tex]W = mg[/tex]

[tex]W = (7.24 \times 10^{-12})(9.81)[/tex]

[tex]W = 7.1 \times 10^{-11}[/tex]

Now electric force on the pollen is given

[tex]F = qE[/tex]

[tex]F = (-0.700\times 10^{-15})(95)[/tex]

[tex]F = 6.65 \times 10^{-14} N[/tex]

now ratio of electric force and weight is given as

[tex]\frac{F}{W} = \frac{6.65 \times 10^{-14}}{7.1 \times 10^{-11}}[/tex]

[tex]\frac{F}{W} = 9.37 \times 10^{-4}[/tex]

An object is originally moving at a constant velocity of 8 m/s in the -x direction. It moves at this constant velocity for 3 seconds. Then, a constant acceleration of 7 m/s2 is applied to it in the +x direction for 9 seconds. What is the total distance covered by this object in meters? Please give a detailed explanation.

Answers

Answer:

244.64m

Explanation:

First, we find the distance traveled with constant velocity. It's simply multiplying velocity time the time that elapsed:

[tex]x = V*t = -8\frac{m}{s} *3s = -24m[/tex]

After this, the ball will start traveling with a constant acceleration motion. Due to the fact that the acceleration is the opposite direction to the initial velocity, this motion will have 2 phases:

1. The velocity will start to decrease untill it reaches 0m/s.

2. Then, the velocity will start to increase at the rate of the acceleration.

The distance that the ball travels in the first phase can be found with the following expression:

[tex]v^2 = v_0^2 + 2a*d[/tex]

Where v is the final velocity (0m/s), v_0 is the initial velocity (-8m/s) and a is the acceleration (+9m/s^2). We solve for d:

[tex]d = \frac{v^2 - v_0^2}{2a} = \frac{(0m/s)^2 - (-8m/s)^2}{2*7m/s^2}= -4.57m[/tex]

Now, before finding the distance traveled in the second phase, we need to find the time that took for the velocity to reach 0:

[tex]t_1 = \frac{v}{a} = \frac{8m/s}{7m/s^2} = 1.143 s[/tex]

Then, the time of the second phase will be:

[tex]t_2 = 9s - t_1 = 9s - 1.143s = 7.857s[/tex]

Using this, we using the equations for constant acceleration motion in order to calculate the distance traveled in the second phase:

[tex]x = \frac{1}{2}a*t^2 + v_0*t + x_0[/tex]

V_0, the initial velocity of the second phase, will be 0 as previously mentioned. X_0, the initial position, will be 0, for simplicity:

[tex]x = \frac{1}{2}*7\frac{m}{s^2}*t^2 + 0m/s*t + 0m = 216.07m[/tex]

So, the total distance covered by this object in meters will be the sum of all the distances we found:

[tex]x_total = 24m + 4.57m + 216.07m = 244.64m[/tex]

A speed skater moving across frictionless ice at 8.4 m/s hits a 5.7 m -wide patch of rough ice. She slows steadily, then continues on at 6.5 m/s. What is her acceleration on the rough ice?

Answers

Answer:

Acceleration, [tex]a=-2.48\ m/s^2[/tex]

Explanation:

Initial speed of the skater, u = 8.4 m/s

Final speed of the skater, v = 6.5 m/s

It hits a 5.7 m wide patch of rough ice, s = 5.7 m

We need to find the acceleration on the rough ice. The third equation of motion gives the relationship between the speed and the distance covered. Mathematically, it is given by :

[tex]v^2-u^2=2as[/tex]

[tex]a=\dfrac{v^2-u^2}{2s}[/tex]

[tex]a=\dfrac{(6.5)^2-(8.4)^2}{2\times 5.7}[/tex]

[tex]a=-2.48\ m/s^2[/tex]

So, the acceleration on the rough ice [tex]-2.48\ m/s^2[/tex] and negative sign shows deceleration.

If the wavelength of an electron is 4.63 x 10^−7 m, how fast is it moving?

Answers

Answer:

it move with velocity 1571 m/s

Explanation:

given data

wavelength λ = 4.63 × [tex]10^{-7}[/tex] m

to find out

how fast is it moving

solution

we will use here de Broglie wavelength equation

that is

wavelength λ = [tex]\frac{h}{mv}[/tex]    ..........1

here h is planck constant = 6.626068 × [tex]10^{-34}[/tex]

and m is mass of electron i.e = 9.10938188 × [tex]10^{-31}[/tex]

and v is velocity

put all value we find velocity  in equation 1

wavelength λ = [tex]\frac{h}{mv}[/tex]  

v = [tex]\frac{6.626068*10^{-34}}{9.10938188*10^{-31}*4.63*10^{-7}}[/tex]

v =  1571.035464

so it move with velocity 1571 m/s

Answer:

[tex]v=1.57*10^{3}\frac{m}{s}[/tex]

Explanation:

As DeBroglie equation proved by Davisson-Germer experiment says, the wavelength of an electron is related with its velocity with the equation:

λ = [tex]\frac{h}{mv}[/tex]

where m is the mass of the electron [tex]m=9.11*10^{-31}kg[/tex], h is the Planck´s constant [tex]h=6.626*10^{-34}J.s[/tex] and v its velocity.

Solving the equation for the velocity of the electron, we have:

v = h/mλ

And replacing the values:

[tex]v=\frac{6.626*10^{-34}J.s}{(9.11*10^{-31}Kg)*(4.63*10^{-7}m)}[/tex]

[tex]v=1570.9\frac{m}{s}[/tex]

[tex]v=1.57*10^{3}\frac{m}{s}[/tex]

Time dilation: A missile moves with speed 6.5-10 m/s with respect to an observer on the ground. How long will it take the missile's clock to fall behind the ground observer's clock by 1 millisecond? Hint: use the binomial formula:(1+x)a1+ ax.

Answers

Answer:

The time taken by missile's clock is [tex]4.6\times 10^{6} s[/tex]

Solution:

As per the question:

Speed of the missile, [tex]v_{m = 6.5\times 10^{3}} m/s[/tex]

Now,

If 'T' be the time of the frame at rest then the dilated time as per the question is given as:

T' = T + 1

Now, using the time dilation eqn:

[tex]T' = \frac{T}{\sqrt{1 + (\frac{v_{m}}{c})^{2}}}[/tex]

[tex]\frac{T'}{T} = \frac{1}{\sqrt{1 + (\frac{v_{m}}{c})^{2}}}[/tex]

[tex]\frac{T + 1}{T} = \frac{1}{\sqrt{1 + (\frac{v_{m}}{c})^{2}}}[/tex]

[tex]1 + \frac{1}{T} = \frac{1}{\sqrt{1 + (\frac{v_{m}}{c})^{2}}}[/tex]

[tex]1 + \frac{1}{T} = (1 + (\frac{v_{m}}{c})^{2})^{- \frac{1}{2}}[/tex]         (1)

Using binomial theorem in the above eqn:

We know that:

[tex](1 + x)^{a} = 1 + ax[/tex]

Thus eqn (1) becomes:

[tex]1 + \frac{1}{T} = 1 - \frac{- 1}{2}.\frac{v_{m}^{2}}{c^{2}}[/tex]

[tex]T = \frac{2c^{2}}{v_{m}^{2}}[/tex]

Now, putting appropriate values in the above eqn:

[tex]T = \frac{2(3\times 10^{8})^{2}}{(6.5\times 10^{3})^{2}}[/tex]

[tex]T = 4.6\times 10^{6} s[/tex]

A spring stretches 0.2 cm per newton of applied force. An object is suspended from the spring and a deflection of 3 cm is observed. If g = 9.81 m/s?, what is the mass of the object, in kg?

Answers

Final answer:

The mass of the object is 1.53 kg.

Explanation:

To find the mass of the object, we need to use Hooke's Law which states that the force exerted by a spring is directly proportional to its extension. In this case, the spring stretches 0.2 cm per newton of applied force. The deflection of 3 cm corresponds to an applied force of 15 newtons (0.2 cm per newton * 3 cm).

Using the equation F = mg, where F is the force, m is the mass, and g is the acceleration due to gravity (9.81 m/s^2), we can find the mass:

15 newtons = m * 9.81 m/s^2

m = 15 newtons / 9.81 m/s^2 = 1.53 kg

Therefore, the mass of the object is approximately 1.53 kg.

The mass of the object is approximately 1.53 kg.

Given that the spring stretches 0.2 cm per newton of applied force. Thus, we can say that

for F = - kx.

1 N = - k (0.2 cm)

or, k = spring constant of the given spring = [tex]\frac{F}{x}[/tex] = 5 N/cm

Now, for an object producing deflection of 3 cm, we can say that:

F = - k x = 5 N/cm × 3 cm

or, F = 15 N

This concludes that the weight of the object is 15 N.

Now, W = F = mg

hence, [tex]m = \frac{F}{g}[/tex]

or, m = [tex]\frac{15 \hspace{0.6mm} N}{9.8 \hspace{0.5mm} m/s^2}[/tex]

or, m ≈ 1.53 kg

A nonconducting container filled with 25 kg of water at 23°C is fitted with a stirrer, which is made to turn by gravity acting on a weight of mass 32 kg. The weight falls slowly through a distance of 5 m in driving the stirrer. Assume that all work done on the weight is transferred to the water and that the local acceleration of gravity is 9.8 m·s−2, determine:
(a) The amount of work done on the water.
(b) The internal-energy change of the water.
(c) The final temperature of the water, for which Cp =4.18 kJ/kgC.
(d) The amount of heat that must be removed from the water to return it to it initial temperature.

Answers

Explanation:

Given that,

Weight of water = 25 kg

Temperature = 23°C

Weight of mass = 32 kg

Distance = 5 m

(a). We need to calculate the amount of work done on the water

Using formula of work done

[tex]W=mgh[/tex]

[tex]W=32\times9.8\times5[/tex]

[tex]W=1568\ J[/tex]

The amount of work done on the water is 1568 J.

(b). We need to calculate the internal-energy change of the water

Using formula of internal energy

The change in internal energy of the water equal to the amount of the  work done on the water.

[tex]\Delta U=W[/tex]

[tex]\Delta U=1568\ J[/tex]

The  change in internal energy is 1568 J.

(c). We need to calculate the final temperature of the water

Using formula of the change internal energy

[tex]\Delta U=mc_{p}\Delta T[/tex]

[tex]\Delta U=mc_{p}(T_{2}-T_{1})[/tex]

[tex]T_{2}=T_{1}+\dfrac{\Delta U}{mc_{p}}[/tex]

[tex]T_{2}=23+\dfrac{1568}{25\times4.18\times10^{3}}[/tex]

[tex]T_{2}=23.01^{\circ}\ C[/tex]

The final temperature of the water is 23.01°C.

(d). The amount of heat removed from the water to return it to it initial temperature is the change in internal energy.

The amount of heat is 1568 J.

Hence, This is the required solution.

Final answer:

The work done on the water is 1568 Joules, which is also the internal-energy change of the water. The final temperature of the water is 23.015°C and to return the water to its initial temperature, 1568 Joules of heat must be removed.

Explanation:

(a) The amount of work done on the water is calculated using the formula for gravitational potential energy which depends on the weight's height, mass and acceleration due to gravity. Therefore, work done= mass × gravity × height = 32 kg × 9.8 m·s−2 × 5 m = 1568 Joules.

(b) As per the Law of Conservation of Energy, the work done on the water is converted completely into the internal energy of the water, so the internal-energy change of the water is 1568 Joules.

(c) The final temperature of the water can be calculated using the formula q = m × c × Δt, where 'q' is heat-transfer, 'm' is mass, 'c' is specific heat capacity and 'Δt' is change in temperature. Rearranging, we find Δt = q /(m × c). Substituting the known values gives Δt = 1568 J /(25 kg × 4.18 kJ/kgC) = 0.015 °C. Adding this to the initial temperature, we find the final temperature of the water is 23.015°C.

(d) To return the water to its initial temperature, the heat equal to the increase in internal energy must be removed. Hence, the amount of heat to be removed from the water = 1568 Joules.

Learn more about Energy Conversion here:

https://brainly.com/question/20458806

#SPJ3

In an experiment, a rectangular block with height h is allowed to float in two separate liquids. In the first liquid, which is water, it floats fully submerged. In the second liquid it floats with height h/7 above the liquid surface. What is the relative density (the density relative to that of water) of the second liquid?

Answers

Answer:

The relative density of the second liquid is 7.

Explanation:

From archimede's principle we know that the force that a liquid exerts on a object equals to the weight of the liquid that the object displaces.

Let us assume that the volume of the object is 'V'

Thus for the liquid in which the block is completely submerged

The buoyant force should be equal to weight of liquid

Mathematically

[tex]F_{buoyant}=Weight\\\\\rho _{1}\times V\times g=m\times g\\\\\therefore \rho _{1}=\frac{m}{V}...............(i)[/tex]

Thus for the liquid in which the block is 1/7 submerged

The buoyant force should be equal to weight of liquid

Mathematically

[tex]F'_{buoyant}=Weight\\\\\rho _{2}\times \frac{V}{7}\times g=m\times g\\\\\therefore \rho _{2}=\frac{7m}{V}.................(ii)[/tex]

Comparing equation 'i' and 'ii' we see that

[tex]\rho_{2}=7\times \rho _{1}[/tex]

Since the first liquid is water thus [tex]\rho _{1}=1gm/cm^3[/tex]

Thus the relative density of the second liquid is 7.

Answer:

7

Explanation:

Let the density of second liquid is d.

Density of water = 1 g/cm^3

In case of equilibrium, according to the principle of flotation, the weight of the body is balanced by the buoyant force acting on the body.

Let A be the area of cross section of block and D be the density of material of block and h be the height.

For first liquid (water):

Weight of block = m x g  = A x h x D x g .... (1)

Buoyant force in water = A x h x 1 x g  ..... (2)

Equating (1) and (2) we get

A x h x D x g = A x h x 1 x g

D = 1 g/cm^3

For second liquid:

Weight of block = m x g  = A x h x D x g .... (1)

Buoyant force in second liquid = A x h/7 x d x g  ..... (2)

Equating (1) and (2) we get

A x h x D x g = A x h/7 x d x g

D = d/7

d = 7 D = 7 x 1 = 7 g/cm^3

Thus, the relative density of second liquid is 7.

A car is going 7 m/s when it begins to accelerate. Sixty meters further down the road, the car is going 24 m/s. a) What was the acceleration of the car? b) How much time did the change from 7 m/s to 24 m/s take?

Answers

Answer:

acceleration = 4.4 m/s²

time is 3.86 s

Explanation:

given data

initial speed = 7 m/s

final speed = 24 m/s

distance = 60 m

to find out

acceleration and time when change speed change

solution

we will apply here equation of motion for acceleration

v²-u² = 2×a×s   .................1

here v is final speed and u is initial speed and s is distance and a is acceleration

put here all these value

24²-7² = 2×a×60

so

a = 4.4

acceleration = 4.4 m/s²

and

now find time by equation of motion

v = u +at

put her value

24 = 7 + 4.4 (t)

t = 3.86

so time is 3.86 s

An airplane in the process of taking off travels with a speed of 80 m/s at an angle of 15° above the horizontal. What is the ground speed of the airplane? O 80 m/s O 21 m/s O 77 m/s O 2.6 m/s

Answers

Answer:

Option C

Explanation:

given,

velocity of airplane = 80 m/s

angle with the horizontal = 15°

speed of the ground= ?

when the plane is taking off the horizontal component of the velocity is v cosθ

so,      

        ground speed of the airplane is = [tex]v\times cos\theta[/tex]

                                                              = [tex]80 \times cos 15^0[/tex]

                                                           v  =  77.27 m/s

horizontal velocity of the air plane comes out to be 77.27 m/s ≅ 77 m/s

so, the correct option is Option C

A man strikes one end of a thin rod with a hammer. The speed of sound in the rod is 15 times the speed of sound in air. A woman, at the other end with her ear close to the rod, hears the sound of the blow twice with a 0.12 s interval between; one sound comes through the rod and the other comes through the air alongside the rod. If the speed of sound in air is 343 m/s, what is the length of the rod?

Answers

Answer:

44.1 m

Explanation:

Given:

[tex]V_a[/tex] = speed of sound in air = 343 m/s[tex]V_r[/tex] = speed of sound in the rod = [tex]15V_a[/tex][tex]\Delta t[/tex] = times interval between the hearing the sound twice = 0.12 s

Assumptions:

[tex]l[/tex] = length of the rod[tex]t[/tex] = time taken by the sound to travel through the rod [tex]T[/tex] = time taken by the sound to travel to through air to the same point = [tex]t+\Delta t = t+0.12\ s[/tex]

We know that the distance traveled by the sound in a particular medium is equal to the product of the speed of sound in that medium and the time taken.

For traveling sound through the rod, we have

[tex]l=V_r t\\\Rightarrow t = \dfrac{l}{V_r}[/tex]..........eqn(1)

For traveling sound through the air to the women ear for traveling the same distance, we have

[tex]l=V_aT\\\Rightarrow l=V_a(t+0.12)\\\Rightarrow l=V_a(\dfrac{l}{V_r}+0.12)\,\,\,\,\,\,(\textrm{From eqn (1)})\\\Rightarrow l=V_a(\dfrac{l}{15V_a}+0.12)\\\Rightarrow l=\dfrac{l}{15}+0.12V_a\\\Rightarrow l-\dfrac{l}{15}=0.12V_a\\\Rightarrow \dfrac{14l}{15}=0.12V_a\\\Rightarrow l = \dfrac{15}{14}\times 0.12V_a\\\Rightarrow l = \dfrac{15}{14}\times 0.12\times 343\\\Rightarrow l = \dfrac{15}{14}\times 0.12\times 343\\\Rightarrow l = 44.1\ m[/tex]

Hence, the length of the rod is 44.1 m.

Final answer:

The length of the rod can be calculated using the difference in hearing times and the speed of sound in the rod and air. Using the formula for distance (speed x time), and given that the speed of sound in the rod is 15 times the speed of sound in air, the length of the rod is found to be approximately 41.16 meters.

Explanation:

In this problem, we know that the speed of sound in the rod is 15 times the speed of sound in the air, and that the woman hears the sound of the strike twice with a 0.12 second gap. The first sound is transmitted through the rod and the second, through the air. Therefore, we can use this information to conclude that the difference in time is the amount of time it takes for the sound to travel the length of the rod in air after it already traveled through the rod.

The speed of sound in the rod is 15 times the speed of sound in air, which is given as 343 m/s. So, the speed of sound in the rod is 15 * 343 = 5145 m/s.

We are looking for the distance travelled, which is the length of the rod. We can find the distance by using the formula distance = speed x time. In this case we are calculating distance as time taken for sound to travel through air minus the time taken to travel through the rod. Therefore, the length of the rod can be calculated to be 343 m/s * 0.12 s = 41.16 meters.

Learn more about Speed of Sound here:

https://brainly.com/question/35989321

#SPJ3

The force of attraction between a -130.0 C and +180.0 C charge is 8.00 N. What is the separation between these two charges in meter rounded to three decimal places? (k = 1/470 - 9.00 10°N.m2/C2 1uC = 106C)

Answers

Answer:

distance between the charges is 5.12 × 10⁶ m

Explanation:

charges q₁ = -130.0 C                

              q₂ = 180 C                  

force between the charges = 8 N

force between two charge                              

   [tex]F = \dfrac{k q_1q_2}{r^2}[/tex]

value of  K =8.975 × 10⁹ N.m²/C²

    [tex]8 = \dfrac{8.975 \times 10^{9}\times 130 \times 180}{r^2}[/tex]

    [tex]r^2 = \dfrac{8.975 \times 10^{9}\times 130 \times 180}{8}[/tex]

    [tex]r^2 =2.625 \times 10^{13} [/tex]

    r = 5.12 × 10⁶  m                                          

hence, distance between the charges is 5.12 × 10⁶ m.

ou drag your feet on a carpeted floor on a dry day and the carpet acquires a net positive charge. a. Will you have an electron deficiency or an excess of electrons?
b. If the load acquired has a magnitude of 2.15 nC, how many elecrtrons were transferred?

Answers

Answer:

1) We will have excess of electrons

2) The number of electrons transferred equals [tex]1.343\times 10^{10}[/tex]

Explanation:

Part a)

Since we know that the charge transfer occurs by the transfer of electrons only as it is given that the carpet has acquired a positive charge it means that it has lost some of the electron's since electrons are negatively charged and if a neutral body looses negative charge it will become positively charged. The electron's that are lost by the carpet will be acquired by the feet of the human thus making us negatively charged.Hence we will gain electrons making us excess in electrons.

Part b)

From charge quantinization principle we have

[tex]Q=ne[/tex]

where

Q = charge of body

n = no of electrons

e = fundamental charge

Applying values in the above equation we get

[tex]2.15\times 10^{-9}C=n\times 1.6\times 10^{-19}C\\\\\therefore n=\frac{2.15\times 10^{-9}C}{1.6\times 10^{-19}C}=1.343\times 10^{10}[/tex]

Ethyl alcohol has a boiling point of 78.0°C, a freezing point of -114°C, a heat of vaporization of 879 kJ/kg, a heat of fusion of 109 kJ/kg, and a specific heat of 2.43 kJ/kg.K. How much energy must be removed from 0.651 kg of ethyl alcohol that is initially a gas at 78.0°C so that it becomes a solid at -114°C?

Answers

Answer:

946.92 kJ

Explanation:

This process has 3 parts:

1. The first part, where the temperature of Ethyl alcohol remains constant and it changes from gas to liquid.

2. The second part, where the temperature drops from 78°C to -114°C

3. The third parts, where the temperature remains constant and it changes from liquid to solid.

The energy lost in a phase change is:

Q = m*cl

The energy lost because of the drop in temperature is:

[tex]Q = m c(T_2-T_1)[/tex]

cl is the heat of vaporization or heat of fusion, depending on the type of phase change. c is the specific heat.

So, the energy lost in each part is:

1. [tex]Q_1 = 0.651kg*879 kJ/kg =  572.23 kJ[/tex]

2. [tex]Q_2 = 0.651kg*2.43 kJ/kgK(78.0^oC - (-114^oC)) = 303.73 kJ[/tex]

3. [tex]Q_3 = 0.651kg*109kJ/kg = 70.96 kJ[/tex]

Then, the total energy removed should be:

Q = Q1 + Q2 + Q3 = 572.23 kJ + 303.73kJ + 70.96kJ = 946.92 kJ

It has been said that in his youth George Washington threw a silver dollar across a river. Assuming that the wide, (a) what minimum initial speed river was 75 m was necessary to get the coin across the river and b) how long was the coin in flight?

Answers

Answer:

(a) 27.1 m/s

(b) 3.9 second

Explanation:

Let the speed is u.

Maximum horizontal range, R = 75 m

The range is maximum when the angle of projection is 45°.

(a) Use the formula for the maximum horizontal range

[tex]R=\frac{u^{2}}{g}[/tex]

[tex]75=\frac{u^{2}}{9.8}[/tex]

u = 27.1 m/s

(b) Let the time of flight is T.

Use the formula for the time of flight

[tex]T=\frac{2uSin\theta}{g}[/tex]

[tex]T=\frac{2\times 27.1 \times Sin45}{9.8}[/tex]

T = 3.9 second

Answer:

A and B

Explanation:

Your throw a ball straight upward at an initial speed of 5 m/s. How many times does the ball pass a point 2 m above the point you launched it from? Draw an x-t and a v-t diagram for the motion of this ball.

Answers

Answer:

The ball never passes 2m high, Hmax=1.27m

Explanation:

we assume the ball doesn't bounce when it hits the ground.

We calculate the maximum height, Vf = 0.

[tex]v_{o}^{2}=2gH_{max}\\H_{max}=v_{o}^{2}/(2g)=5^{2}/(2*9.81)=1.27m[/tex]

So, the ball never passes 2m high.

Kinematics equations:

[tex]x(t)=v_{o}t-1/2*g*t^{2}\\v(t)=v_{o}-gt[/tex]

Find annexed the graphics of x(t) and v(t)

Two tiny conducting sphere are identical and carry charges of -20 μC and +50 μC. They are separated by a distance of 2.50 cm. What is the magnitude of the force that each sphere experiences, and is the force attractive or repulsive?

Answers

Answer:

Force between two spheres will be 14400 N

And as the both charges of opposite nature so force will be attractive

Explanation:

We have given two conducting spheres of charges [tex]q_1=-20\mu C=-20\times 10^{-6}C\ and\ q_2=50\mu C=50\times 10^{-6}C[/tex]

Distance between the spheres = 2.5 cm =0.025 m

According to coulombs law we know that force between two charges is given by [tex]F=\frac{1}{4\pi \varepsilon _0}\frac{q_1q_2}{r^2}=\frac{Kq_1q_2}{r^2}=\frac{9\times 10^9\times 20\times 10^{-6}\times 50\times 10^{-6}}{0.025^2}=14400N[/tex]  

As the both charges of opposite nature so force will be attractive

Your hair grows at the rate of 0.0330 mm/hr. What is the rate of your hair growth in ft/year?

Answers

Answer: 0.95 ft/year

Explanation: In order to explain this question we have to convert the units so

if we have a rate equal to 0.033 mm/hr then 0.033 mm *24*365 hr/year

then 1 m=3.28 feet

8760*0.033 *10^-3m* 3.28 feet/m=1.08*10^-4 feet*8760=0.95 feet/year

Calculate the individual positive plate capacity in motive power cell that has 15 plates and a copa of 595 Ah A. 110 Ah B. 75 Ah C. 90 Ah D. 85 Ah

Answers

Answer:

The individual positive plate capacity is 85 Ah.

(D) is correct option.

Explanation:

Given that,

Number of plates = 15

Capacity = 595 Ah

We need to calculate the individual positive plate capacity in motive power cell

We have,

15 plates means 7 will make pair of positive and negative.

So, there are 7 positive cells individually.

The capacity will be

[tex]capacity =\dfrac{power}{number\ of\ cells}[/tex]

Put the value into the formula

[tex]capacity =\dfrac{595}{7}[/tex]

[tex]capacity =85\ Ah[/tex]

Hence, The individual positive plate capacity is 85 Ah.

Answer:

SDFGHJKL

Explanation:

If the Earth’s crust contained twice as much iron as it does, would atmospheric oxygen buildup have been slowed down or sped up during the past 2.5 billion years?

What would the consequence of this have been for the evolution of aerobic respiration, the ozone layer, green plants, and animals?

Answers

No oxygen levels do to secretion of atmosphere

A test charge of +4 µC is placed halfway between a charge of +6 µC and another of +2 µC separated by 20 cm. (a) What is the magnitude of the force (in N) on the test charge?
(b) What is the direction of this force (away from or toward the +6 µC charge)?
a. away from the +6 µC charge or
b. toward the +6 µC charge

Answers

Answer:

(a) Magnitude: 14.4 N

(b) Away from the +6 µC charge

Explanation:

As the test charge has the same sign, the force that the other charges exert on it will be a repulsive force. The magnitude of each of the forces will be:

[tex]F_e = K\frac{qq_{test}}{r^2}[/tex]

K is the Coulomb constant equal to 9*10^9 N*m^2/C^2, q and qtest is the charge of the particles, and r is the distance between the particles.

Let's say that a force that goes toward the +6 µC charge is positive, then:

[tex]F_e_1 = K\frac{q_1q_{test}}{r^2}=-9*10^9 \frac{Nm^2}{C^2} \frac{6*10^{-6}C*4*10^{-6}C}{(0.1m)^2} =-21.6 N[/tex]

[tex]F_e_2 = K\frac{q_2q_{test}}{r^2}=9*10^9 \frac{Nm^2}{C^2} \frac{2*10^{-6}C*4*10^{-6}C}{(0.1m)^2} =7.2 N[/tex]

The magnitude will be:

[tex]F_e = -21.6 + 7.2 = -14.4 N[/tex], away from the +6 µC charge

What does it mean if a conductor is in "electrostatic equilibrium"? a) The conductor is at rest.
b) The charges in the conductor are not moving.
c) The charges in the conductor are distributed uniformly throughout the conductor.
d) The charges in the conductor are moving in response to an electric field.
e) None of the above.

Answers

Answer:

25

Explanation:

A bullet has a mass of 8 grams and a muzzle velocity of 340m/sec. A baseball has a mass of 0.2kg and is thrown by the pitcher at 40m/sec. What is the momentum of the baseball? What is the momentum of the bullet?

Answers

Answer:

Momentum of bullet

[tex]P = 2.72 kg m/s[/tex]

momentum of baseball

[tex]P = 8 kg m/s[/tex]

Explanation:

As we know that momentum is defined as the product of mass and velocity

here we know that

mass of the bullet = 8 gram

velocity of bullet = 340 m/s

momentum of the bullet is given as

[tex]P = mv[/tex]

[tex]P = (\frac{8}{1000})(340)[/tex]

[tex]P = 2.72 kg m/s[/tex]

Now we have

mass of baseball = 0.2 kg

velocity of baseball = 40 m/s[/tex]

momentum of baseball is given as

[tex]P = (0.2)(40)[/tex]

[tex]P = 8 kg m/s[/tex]

Suppose you are sitting on a rotating stool holding a 2 kgmass
in each outstretched hand. If you suddenly drop the masses,will
your angular velocity increase, decrease, or stay the same?Please
Explain.

Answers

Answer:Increase

Explanation:

Given

You are holding 2 kg mass in each outstreched hand

If the masses are dropped then Moment of inertia will decease by [tex]2mr^2[/tex]

Where m=2 kg

r=length of stretched arm

Since angular momentum is conserved therefore decrease in Moment of inertia will result in increase of angular velocity

as I[tex]\omega [/tex]=constant

I=Moment of inertia

[tex]\omega [/tex]=angular velocity

An inflatable raft (unoccupied) floats down a river at an approximately constant speed of 5.6 m/s. A child on a bridge, 71 m above the river, sees the raft in the river below and attempts to drop a small stone onto the raft. The child releases the stone from rest. In order for the stone to hit the raft, what must be the horizontal distance between the raft and the bridge when the child releases the stone?

Answers

Answer:

21.28 m

Explanation:

height, h = 71 m

velocity of raft, v = 5.6 m/s

let the time taken by the stone to reach to raft is t.

use second equation of motion for stone

[tex]h = ut + \frac{1}{2}at^{2}[/tex]

u = 0 m/s, h = 71 m, g = 9.8 m/s^2

71 = 0 + 0.5 x 9.8 x t^2

t = 3.8 s

Horizontal distance traveled by the raft in time t

d = v x t = 5.6 x 3.8 = 21.28 m

A grasshopper makes four jumps. The displacement vectors are (1) 31.0 cm, due west; (2) 26.0 cm, 44.0 ° south of west; (3) 22.0 cm, 56.0 ° south of east; and (4) 23.0 cm, 75.0 ° north of east. Find (a) the magnitude and (b) direction of the resultant displacement. Express the direction as a positive angle with respect to due west.

Answers

Answer:

(a) 34.47 cm

(b) [tex]24.09^\circ[/tex] south of west

Explanation:

Let us draw a figure representing the individual displacement vectors in the four jumps as shown in the figure attached with this solution.

Now, let us try to write the four displacement vectors in in terms of unit vectors along the horizontal and the vertical axis.

[tex]\vec{d}_1= 31\ cm\ west = -31\ cm\ \hat{i}\\\vec{d}_2= 26\ cm\ south\ of\ west = -26\cos 44^\circ\ \hat{i} -26 \sin 44^\circ\ \hat{j}=(-18.72\ \hat{i}-18.06\ \hat{i})\ cm\\\vec{d}_3= 22\ cm\ south\ of\ east = 22\cos 56^\circ\ \hat{i} -22 \sin 56^\circ\ \hat{j}=(12.30\ \hat{i}-18.23\ \hat{i})\ cm\\\vec{d}_4= 23\ cm\ north\ of\ east = 23\cos 75^\circ\ \hat{i} +23\sin \sin 75^\circ\ \hat{j}=(5.95\ \hat{i}+22.22\ \hat{i})\ cm\\[/tex]

Now, the vector sum of all these vector will give the resultant displacement vector.

[tex]\vec{D} = \vec{d}_1+\vec{d}_2+\vec{d}_3+\vec{d}_4\\\Rightarrow \vec{D} = -31\ cm\ \hat{i}+(-18.72\ \hat{i}-18.06\ \hat{i})\ cm+(12.30\ \hat{i}-18.23\ \hat{i})\ cm+(5.95\ \hat{i}+22.22\ \hat{i})\ cm\\\Rightarrow \vec{D} =(-31.47\ \hat{i}-14.07\ \hat{i})\ cm[/tex]

Part (a):

The magnitude of the resultant displacement vector is given by:

[tex]D=\sqrt{(-31.47)^2+(-14.07)^2}\ m = 34.47\ m[/tex]

Part (b):

Since the resultant displacement vector indicates that the final position of the vector lies in the third quadrant, the vector will make some positive angle in the direction south of west given by:

[tex]\theta = \tan^{-1}(\dfrac{14.07}{31.47})= 24.09^\circ[/tex]

Final answer:

To find the resultant displacement of the grasshopper, we can break down the vectors into their x and y components, and then sum up the components separately. After performing the calculations, we find that the magnitude of the resultant displacement is approximately 39.4 cm and the direction is approximately 38.3° south of west.

Explanation:

To find the resultant displacement of the grasshopper, we need to add the individual displacement vectors. We can do this by breaking down each vector into its x and y components.

For vector (1) with a magnitude of 31.0 cm due west, the x component is -31.0 cm and the y component is 0.

Similarly, for the other vectors, the x and y components are:

(2): x = -26.0*cos(44.0) cm, y = -26.0*sin(44.0) cm(3): x = 22.0*cos(56.0) cm, y = -22.0*sin(56.0) cm(4): x = 23.0*cos(75.0) cm, y = 23.0*sin(75.0) cm

Now, we can sum up the x components and y components separately to find the resultant displacement.

The magnitude of the resultant displacement can be found using the formula:

resultant magnitude = sqrt((sum of x components)^2 + (sum of y components)^2)

The direction of the resultant displacement can be found using the formula:

resultant direction = atan2((sum of y components), (sum of x components))

Plugging in the values and performing the calculations, we find that the magnitude of the resultant displacement is approximately 39.4 cm and the direction of the resultant displacement is approximately 38.3° south of west.

Other Questions
If a 100 m. diameter wind turbine is exposed to 7 m/s wind with an air density of 1.25 kg/m what is the electricity produced by the turbine? Assume a 32% efficiency of the turbine. What mass of steam at 100C must be mixed with 499 g of ice at its melting point, in a thermally insulated container, to produce liquid water at 33.0C? The specific heat of water is 4186 J/kgK. The latent heat of fusion is 333 kJ/kg, and the latent heat of vaporization is 2256 kJ/kg. 1. In triangle ABC, the measure of angle A is 40.a. Give possible measures for angles B and C if triangle ABC is isosceles. Solve the initial value problem y" 4y' - 5y = 0, y(-1) = 3, y'(-1) = 9. Simplify 332x^4 zAssume x and z are nonnegative 4 4/5 4A. -1 1/5B. -4/5C. 4/5D. 1 1/5 Windsor, Inc. has the following transactions during August of the current year. Indicate (a) the effect on the accounting equation and (b) the debit-credit analysis. Aug. 1 Opens an office as a financial advisor, investing $4,100 in cash in exchange for common stock. 4 Pays insurance in advance for 6 months, $1,850 cash. 16 Receives $400 from clients for services performed. 27 Pays secretary $1,760 salary. Marta gasto $60 en la compra de cuadernos iguales si cada cuaderno hubiera costado $2 ms Marta hubiera adquirido 80 cuadernos menos por los mismos $60 Cuntos cuadernos compr Marta? Juliana: Quiero practicar un ejercicio de flexibilidad y concentracin. Marta: Te recomiendo que practiques ___________. A. tenis B. aerbicos C. yoga D. natacin A pure crystalline substance has no movement at absolute zero temperature. O 1st Law of Thermodynamics O 3rd Law of Thermodynamics O Law of Absolute Zero 2nd Law of Thermodynamics Can you sequence the steps in the eutrophication process that occurs in a body of water Part A Drag each statement to the appropriate location in the flowchart of the eutrophication process. Nutrients promote More phytoplankton phytoplankton die and settle to the growth, and bottom, where they Nutrients enter a Aquatic life in and waterway in near the sediment elevated increase are metabolized by flees or suffocates. phytoplankton concentrations. bacteria. density in waters. Hypoxic conditions arise in the deep water above the sediments. g A four-input digital circuit is used to detect whether the resulting product of two two-bits numbers is greater or equal than 3. Consider that the two-bit numbers are given as the inputs BA and DC. So, your design will implement a function X (D, C, B, A) that is "0" if the product of BA X DC is less than 3 and "1" if it is greater or equal than 3. For example if your inputs are (D, C, B, A) = 1010, then the result value is "1" (X (D, C, B, A) =1), since BA =10 (210 ) and DC =10 (210)and the product will be 4, which is greater or equal than 3. On the other hand, if for example, (D, C, B, A) = 1001 then (X (D, C, B, A)=0), since BA =01 (110) and DC =10 (210) with a product equals to 2. The minterm expression for the function X (D, C, B, A) is: A carpenter finds that if she charges p dollars for a chair, she sells 600 3p of them each year.How much should she charge to maximize her annual revenue? Mary is an adolescent who currently has a small pimple on her cheek that is causing her to be overly self-conscious. She is convinced that everyone she meets stares at and talks about her pimple. Mary's behavior exhibits ____________.a. sense of idealism b. imaginary audience c. personal fable d. puberty internalization During the contraction phase of the cardiac cycle, the hearta. pumpls blood to the bodyb. repolarizesc. rests and recoversd. refills How much heat to change 1 mole of ice at -25 C to steam at +125 C? heat to warm ice - heat to melt ice (no temperature change) - heat to warm water heat to boil water (no temperature change) - heat to warm steam Consider the following statement: "If negative emotions cause aggression, and if frustration induces a negative emotion, then frustration must cause aggression." This statement illustrates which one of the following ways of knowing?a. scienceb. authorityc. common sensed. logic What day does adult Lizabeth remember so clearly? Review the following inferences and tell me if you consider them valid conclusions one can draw from the give information. i. If the moon is made of green cheese, then cows jump over it. The moon is made of green cheese, Therefore, cows jump over the moon. ii. If Socrates was a philosopher then he wasn't a historian. Socrates wasn't a historian. So, Socrates was a philosopher. Note: I may not grade this question. The only reason you are asked to solve them is for me to get a feel for the mathematical maturity of the members of this class. Which technique most clearly minimizes the likelihood that any outcome differences between the experimental and control groups can be attributed to age or personality differences in research participants?a. the double-blind procedureb. statistical measurementc. replicationd. operational definitionse. random assignment