An electron enters a region of uniform electric field with an initial velocity of 50 km/s in the same direction as the electric field, which has magnitude E = 50 N/C, (a) what is the speed of the electron 1.5 ns after entering this region? (b) How far does the electron travel during the 1.5 ns interval?

Answers

Answer 1

Answer:

(a). The speed of the electron is [tex]3.68\times10^{4}\ m/s[/tex]

(b). The distance traveled by the electron is [tex]4.53\times10^{-5}\ m[/tex]

Explanation:

Given that,

Initial velocity = 50 km/s

Electric field  = 50 N/C

Time = 1.5 ns

(a). We need to calculate the speed of the electron 1.5 n s after entering this region

Using newton's second law

[tex]F = ma[/tex].....(I)

Using formula of electric force

[tex]F = qE[/tex].....(II)

from equation (I) and (II)

[tex]-qE= ma[/tex]

[tex]a = \dfrac{-qE}{m}[/tex]

(a). We need to calculate the speed of the electron

Using equation of motion

[tex]v = u+at[/tex]

Put the value of a in the equation of motion

[tex]v = 50\times10^{3}-\dfrac{1.6\times10^{-19}\times50}{9.1\times10^{-31}}\times1.5\times10^{-9}[/tex]

[tex]v=36813.18\ m/s[/tex]

[tex]v =3.68\times10^{4}\ m/s[/tex]

(b). We need to calculate the distance traveled by the electron

Using formula of distance

[tex]s = ut+\dfrac{1}{2}at^2[/tex]

Put the value in the equation

[tex]s = 3.68\times10^{4}\times1.5\times10^{-9}-\dfrac{1}{2}\times\dfrac{1.6\times10^{-19}\times50}{9.1\times10^{-31}}\times(1.5\times10^{-9})^2[/tex]

[tex]s=0.0000453\ m[/tex]

[tex]s=4.53\times10^{-5}\ m[/tex]

Hence, (a). The speed of the electron is [tex]3.68\times10^{4}\ m/s[/tex]

(b). The distance traveled by the electron is [tex]4.53\times10^{-5}\ m[/tex]


Related Questions

A race car has a speed of 80 m/s when the driver releases a drag parachute. If the parachute causes a deceleration of 4m/s^2, how far will the car travel before it stops?

Answers

Answer:

The car travels 800m

Explanation:

We will need two formulas to solve this question:

[tex]V_{f}=V_{0}+at\\X=V_{0}t+\frac{at^{2}}{2}[/tex]

We can obtain the the time by using the final velocity formula and replacing with known values:

[tex]V_{f}=V_{0}+at\\\\0\frac{m}{s}=80\frac{m}{s}-4\frac{m}{s^{2}}t\\\\4\frac{m}{s^{2}}t=80\frac{m}{s}\\t=20 s[/tex]

Since we know the time, the question will be answered by inputing all the variables needed in the distance formula:

[tex]X=V_{0}t+\frac{at^{2}}{2}\\\\X=80\frac{m}{s}(20s)-\frac{4(20s)^{2}}{2}=800m[/tex]

Final answer:

The race car will travel 800 meters before coming to a stop after deploying a drag parachute causing a deceleration of 4 m/s^2 from an initial speed of 80 m/s.

Explanation:

To calculate how far the race car will travel before it stops after deploying a drag parachute, we can use the kinematic equation that relates initial velocity, final velocity, acceleration, and distance traveled. Considering that the deceleration is constant, the kinematic equation we can use is v2 = u2 + 2as, where v is the final velocity, u is the initial velocity, a is the acceleration, and s is the distance traveled.

Since the car comes to a stop, v = 0 m/s. The initial speed is u = 80 m/s and the deceleration provided by the drag parachute is a = -4 m/s2 (negative because it's deceleration). Plugging these values into the equation gives us:

0 = (80 m/s)2 + 2(-4 m/s2)s

Solving for s, we find:

s = (80 m/s)2 / (2 * 4 m/s2)

s = 6400 m2/s2 / 8 m/s2

s = 800 meters

Therefore, the race car will travel 800 meters before coming to a stop after the drag parachute is deployed.

Which properties should an object, system, or process have in order for it to be a useful standard of measurement for a physical quantity such as length or time? (Choose all that apply) -precise-restricted availability-defined in SI units-small-reproducible

Answers

Answer:

Precise and Reproducible

Explanation:

For a system or a process to be useful a measurement standard for any physical quantity, it must be:

Precise, Precision is important in any measurement.The values of the measurement obtained should be reproducibleThe measurement may be large or smallIt may or may not be in SI unitsIt should be available easily.

Answer:

precise

reproducible

Explanation:

An engine extracts 441.3kJ of heat from the burning of fuel each cycle, but rejects 259.8 kJ of heat (exhaust, friction,etc) during each cycle. What is the thermal efficiency of the engine?

Answers

Answer:

[tex]\eta = 0.411[/tex]

Explanation:

As we know that efficiency is defined as the ratio of output useful work and the input energy to the engine

So here we know that the

input energy = 441.3 kJ

energy rejected = 259.8 kJ

so we have

[tex]Q_1 - Q_2 = W[/tex]

[tex]W = 441.3 kJ - 259.8 kJ = 181.5 kJ[/tex]

now efficiency is defined as

[tex]\eta = \frac{W}{Q_1}[/tex]

[tex]\eta = \frac{181.5}{441.3}[/tex]

[tex]\eta = 0.411[/tex]

A small rock is thrown vertically upward with a speed of 27.0 m/s from the edge of the roof of a 21.0-m-tall building. The rock doesn't hit the building on its way back down and lands in the street below. Ignore air resistance. Part A: What is the speed of the rock just before it hits the street?
Part B: How much time elapses from when the rock is thrown until it hits the street?

Answers

Answer:

A. 33.77 m/s

B. 6.20 s

Explanation:

Frame of reference:

Gravity g=-9.8 m/s^2; Initial position (roof) y=0; Final Position street y= -21 m

Initial velocity upwards v= 27 m/s

Part A. Using kinematics expression for velocities and distance:

[tex]V_{final}^{2}=V_{initial}^{2}+2g(y_{final}-y_{initial})\\V_{f}^{2}=27^{2}-2*9.8(-21-0)=33.77 m/s[/tex]

Part B. Using Kinematics expression for distance, time and initial velocity

[tex]y_{final}=y_{initial}+V_{initial}t+\frac{1}{2} g*t^{2}\\==> -0.5*9.8t^{2}+27t+21=0\\==> t_1 =-0.69 s\\t_2=6.20 s[/tex]

Since it is a second order equation for time, we solved it with a calculator. We pick the positive solution.

Final answer:

The speed of the rock just before it hits the street is approximately 20.3 m/s, and the time elapsed from when the rock is thrown until it hits the street is approximately 5.5 seconds.

Explanation:

Part A: To determine the speed of the rock just before it hits the street, we can use the concept of conservation of energy. When the rock is at the top of its trajectory, its potential energy is at its maximum and its kinetic energy is at its minimum. When the rock is just before hitting the street, its potential energy is at its minimum (zero) and its kinetic energy is at its maximum. Using the equations for potential energy and kinetic energy, we can calculate the speed of the rock:

Initial potential energy = final potential energy + final kinetic energy

mgh = 1/2m*v^2

where m is the mass of the rock, g is the acceleration due to gravity, h is the height of the building, and v is the final velocity of the rock.

Since the mass of the rock cancels out, we have:

gh = 1/2v^2

Plugging in the values, g = 9.8 m/s^2 and h = 21.0 m, we can solve for v:

v = sqrt(2gh)

v = sqrt(2*9.8*21.0)

v = sqrt(411.6)

v = 20.3 m/s

Therefore, the speed of the rock just before it hits the street is approximately 20.3 m/s.

Part B: To calculate the time elapsed from when the rock is thrown until it hits the street, we can use the equation for time of flight of a vertically thrown object:

t = 2v/g

where t is the time of flight, v is the initial upward velocity of the rock, and g is the acceleration due to gravity.

Plugging in the values, v = 27.0 m/s and g = 9.8 m/s^2, we can solve for t:

t = 2*27.0/9.8

t = 5.5 s

Therefore, the time elapsed from when the rock is thrown until it hits the street is approximately 5.5 seconds.

What is the wavelength of a monochromatic light beam, where the photon energy is 2.70 × 10^−19 J? (h = 6.63 ×10^−34 J⋅s, c = 3.00 × 10^8 m/s, and 1 nm = 10^−9 m)

Answers

Answer:

Wavelength = 736.67 nm

Explanation:

Given

Energy of the photon = 2.70 × 10⁻¹⁹ J

Considering:

[tex]Energy=h\times frequency[/tex]

where, h is Plank's constant having value as 6.63 x 10⁻³⁴ J.s

The relation between frequency and wavelength is shown below as:

c = frequency × Wavelength

Where, c is the speed of light having value = 3×10⁸ m/s

So, Frequency is:

Frequency = c / Wavelength

So,  Formula for energy:

[tex]Energy=h\times \frac {c}{\lambda}[/tex]

Energy = 2.70 × 10⁻¹⁹ J

c = 3×10⁸ m/s

h = 6.63 x 10⁻³⁴ J.s

Thus, applying in the formula:

[tex]2.70\times 10^{-19}=6.63\times 10^{-34}\times \frac {3\times 10^8}{\lambda}[/tex]

Wavelength = 736.67 × 10⁻⁹ m

1 nm = 10⁻⁹ m

So,

Wavelength = 736.67 nm

A student is driving to school on a road with a speed limit of 40mph (17.9 m/s). A stoplight ahead of her turns yellow, so she begins to slow down to come to a stop. On a dry day, she is able to make her car slow down with an acceleration of magnitude of 8.8 m/s^2. However, if the road is wet, she can only manage an acceleration with a magnitude 3.9 m/s^2. Part A:
On a dry day, how far (in meters) from the intersection would the student need to start braking in order to stop in time?
Part B:
If it were raining instead, how far (in meters) from the intersection would the student need to start braking?

Answers

Answer:

18.21 m

41.1 m

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration

Part A

[tex]v^2-u^2=2as\\\Rightarrow s=\frac{v^2-u^2}{2a}\\\Rightarrow s=\frac{0^2-17.9^2}{2\times -8.8}\\\Rightarrow s=18.21\ m[/tex]

On a dry day she would have to start braking 18.21 m away from the intersection

Part B

[tex]v^2-u^2=2as\\\Rightarrow s=\frac{v^2-u^2}{2a}\\\Rightarrow s=\frac{0^2-17.9^2}{2\times -3.9}\\\Rightarrow s=41.1\ m[/tex]

On a wet day she would have to start braking 41.1 m away from the intersection

During the _____ developmental stage children are drawing their thoughts instead of merely observations.

A. scribbling

B. Schematic

C. circular

D. pre schematic

Answers

Answer:

D. pre schematic

Explanation:

During the _pre schematic____ developmental stage children are drawing their thoughts instead of merely observations.

Pre schematic stage in children is the age at which they drawing, symbols, spatial figures to express themselves. Their becomes more complex and full of lines as they age. They use single base lines, multiple base lines and fold up views.

What uniform magnetic field, applied perpendicular to a beam
ofelectrons moving at 1.30 x 106 m/s, is required to
makethe elctrons travel in a ciruclar arc of radius 0.350 m?

Answers

Answer:

The magnetic field is [tex]2.11\times10^{-5}\ T[/tex]

Explanation:

Given that,

Speed [tex]v=1.30\times10^{6}\ m/s[/tex]

Radius = 0.350 m

We need to calculate the magnetic field

Using formula of magnetic field

[tex]B =\dfrac{mv}{qr}[/tex]

Where, m = mass of electron

v = speed of electron

q = charge of electron

r = radius

Put the value into the formula

[tex]B=\dfrac{9.1\times10^{-31}\times1.30\times10^{6}}{1.6\times10^{-19}\times0.350}[/tex]

[tex]B=2.11\times10^{-5}\ T[/tex]

Hence, The magnetic field is [tex]2.11\times10^{-5}\ T[/tex]

A particle (q = 3.0 mC, m = 20 g) has a speed of 20 m/s when it enters a region where the electric field has a constant magnitude of 80 N/C and a direction which is the same as the velocity of the particle. What is the speed of the particle 3.0 s after it enters this region?

Answers

Answer:

56 m/s

Explanation:

The electirc force applied on the particle by the field will be

F = q * E

F = 3*10^-3 * 80 = 0.24 N

This force will cause an acceleration:

F = m * a

a = F/m

a = 0.24 / 0.02 = 12 m/s^2

The equation for speed under constant acceleration is:

V(t) = V0 + a*t

V(3) = 20 + 12 * t = 56 m/s

The final speed will be  56 m/s.

Two blocks of weight 3.0N and 7.0N are connected by a massless string and slide down a 30 degree inclined plane. The coefficient of kinetic friction between the lighter block and the plane is 0.13; that between the heavier block and the plane is 0.31. Assuming that the lighter block leads, find (a) the magnitude of the acceleration of the blocks and (b) the tension in the string

Answers

Answer:

a. a = [tex]6.41 m/s^2[/tex]

b. T = -0.81 N

Explanation:

Given,

weight of the lighter block = [tex]w_1\ =\ 3.0\ N[/tex]weight of the heavier block = [tex]w_2\ =\ 7.0\ N[/tex]inclination angle = [tex]\theta\ =\ 30^o[/tex]coefficient of kinetic friction between the lighter block and the surface = [tex]\mu_1\ =\ 0.13[/tex]coefficient of kinetic friction between the heavier block and the surface = [tex]\mu_2\ =\ 0.31[/tex]friction force on the lighter block = [tex]f_1\ =\ \mu_1N_1\ =\ \mu_1 w_1cos\theta[/tex]friction force on the heavier block = [tex]f_2\ =\ \mu_2N_2\ =\ \mu_2w_2cos\theta[/tex]

Let 'a' be the acceleration of the blocks and 'T' be the tension in the string.

From the f.b.d. of the lighter block,

[tex]w_1sin\theta\ -\ T\ -\ f_1\ =\ \dfrac{w_1a}{g}\\\Rightarrow T\ =\ w_1sin\theta\ -\ \dfrac{w_1a}{g}\ -\ f_1\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,eqn (1)[/tex]

From the f.b.d. of the heavier block,

[tex]w_2sin\theta\ +\ T\ -\ f_2\ =\ \dfrac{w_2a}{g}\\\Rightarrow T\ =\ \dfrac{w_2a}{g}\ -\ w_2sin\theta\ -\ f_2\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,eqn (2)[/tex]

From eqn (1) and (2), we get,

[tex]w_1sin\theta\ -\ \dfrac{w_1a}{g}\ -\ f_1\ =\ \dfrac{w_2a}{g}\ -\ w_2sin\theta\ -\ f_2\\\Rightarrow w_1gsin\theta \ -\ w_1a\ -\ \mu_1w_1gcos\theta\ =\ w_2a\ -\ w_2gsin\theta\ -\ \mu_2 w_2gcos\theta\\[/tex]

[tex]\Rightarrow a\ =\ \dfrac{g(w_1sin\theta\ -\ \mu_1w_1cos\theta\ +\ w_2sin\theta\ +\ \mu_2w_2cos\theta)}{w_1\ +\ w_2}\\\Rightarrow a\ =\ \dfrac{g[sin\theta(w_1\ +\ w_2)\ +\ cos\theta(\mu_2w_2\ -\ \mu_1w_1)]}{w_1\ +\ w_2}\\[/tex]

[tex]\Rightarrow a\ =\ \dfrac{9.81\times [sin30^o\times (3.0\ +\ 7.0)\ +\ cos30^o\times (0.31\times 7.0\ -\ 0.13\times 3.0)]}{3.0\ +\ 7.0}\\\Rightarrow a\ =\ 6.4\ m/s.[/tex]

part (b)

From the eqn (2), we get,[tex]T\ =\ \dfrac{w_2a}{g}\ -\ w_2sin\theta\ -\ \mu_2w_2cos\theta\\\Rightarrow T\ =\ \dfrac{7.0\times 6.41}{9.81}\ -\ 7.0\times sin30^o\ -\ 0.31\times 7.0\times cos30^o\\\Rightarrow T\ =\ -0.81\ N[/tex]

Answer:

(a) 2.793 m/s^2

(b) 0.335 N

Explanation:

Let a be the acceleration in the system and T be the tension in the string.

W1 = 3 N

W2 = 7 N

m1 = 3 /1 0 = 0.3 kg

m2 = 7 / 10 = 0.7 kg

θ = 30°

μ1 = 0.13, μ2 = 0.31

Let f1 be the friction force acting on block 1 and f2 be the friction force acting on block 2.

By the laws of friction

f1 = μ1 x N1

Where, N1 be the normal reaction acting on block 1.

So, f1 = 0.13 x W1 Cosθ = 0.13 x 3 x cos 30 = 0.337 N

By the laws of friction

f2 = μ2 x N2

Where, N2 be the normal reaction acting on block 2.

So, f2 = 0.31 x W2 Cosθ = 0.31 x 7 x cos 30 = 1.88 N

Apply Newton's second law for both the blocks

W1 Sin30 - T - f1 = m1 a

3 Sin 30 - T - 0.337 = 0.3 x a

1.163 - T = 0.3 a ..... (1)

W2 Sin30 + T - f2 = m2 a

7 Sin30 + T - 1.88 = 0.7 x a

1.62 + T = 0.7 a ..... (2)

By solving equation (1) and (2) we get

a = 2.793 m/s^2

(b) Put the value of a in equation (2), we get

1.62 + T = 0.7 x 2.793

T = 0.335 N

A truck covers 47.0 m in 8.60 s while smoothly slowing down to final speed of 2.30 m/s. (a) Find its original speed.

Answers

Explanation:

Given that,

Distance, s = 47 m

Time taken, t = 8.6 s

Final speed of the truck, v = 2.3 m/s

Let u is the initial speed of the truck and a is its acceleration such that :

[tex]a=\dfrac{v-u}{t}[/tex].............(1)

Now, the second equation of motion is :

[tex]s=ut+\dfrac{1}{2}at^2[/tex]

Put the value of a in above equation as :

[tex]s=ut+\dfrac{1}{2}\times \dfrac{v-u}{t}\times t^2[/tex]

[tex]s=\dfrac{t(u+v)}{2}[/tex]

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

[tex]u=\dfrac{2\times 47}{8.6}-2.3[/tex]

u = 8.63 m/s

So, the original speed of the truck is 8.63 m/s. Hence, this is the required solution.

Aaron is flying a helicopter with an air-relative velocity of 12.5 m/s to the West. A constant wind is also blowing the helicopter towards the South at 4.55 m/s relative to the ground. What is the velocity vector of the helicopter relative to the ground? What is the speed and direction relative to the East? How long does it take to travel 1 km?

Answers

Answer:

Explanation:

Given

Velocity of helicopter relative to air 12.5 m/s to west

In vector form

[tex]V_{ha}=-12.5\hat{i}[/tex]

where [tex]V_h[/tex]= velocity of helicopter relative to ground

Also the velocity of air

[tex]V_a=4.55\hat{j}[/tex]

[tex]V_{ha}=V_h-V_a[/tex]

[tex]V_h=V_{ha}+V_a[/tex]

[tex]V_h=-12.5\hat{i}+4.55\hat{j}[/tex]

Speed relative to east[tex]=\sqrt{12.5^2+4.55^2}[/tex]

=13.302

For Direction

[tex]tan\theta =\frac{4.55}{-12.5}[/tex]

[tex]180-\theta =20[/tex]

[tex]\theta =160^{\circ}[/tex] relative to east

For 1 km travel it takes

[tex]t=\frac{1000}{13.302}=75.17 s[/tex]

A 0.5 kg block is attached to a spring (k = 12.5 N/m). The damped frequency is 0.2% lower than the natural frequency, (a) What is the damping constant? (b) How does the amplitude vary with time? (c) Determine the critical damping constant?

Answers

Final answer:

For a mass-spring system with specified parameters, the damping constant is found to be 4.999 Ns/m. The amplitude reduces exponentially over time. The critical damping constant, defining the transition from underdamped to overdamped behavior, is 5 Ns/m.

Explanation:

This problem pertains to a system of mass springs undergoing damped oscillations. The damping constant (b) can be calculated using the formula b = 2*m*ωd. Here ωd signifies the damped frequency and is given by ωd = ω * (1 - γ/2), where ω is the natural frequency and γ is the damping ratio of 0.2% = 0.002. The natural frequency ω = sqrt(k/m) = sqrt(12.5/0.5) = 5 rad/s. Substituting these values in the equation gives b = 2*0.5*4.999 = 4.999 Ns/m.

The amplitude (A) of a damped oscillation decreases exponentially with time due to energy loss, described by A(t) = A0 * e^(-γωt/2), wherein A0 is the initial amplitude.

The critical damping constant (bc), describing the boundary between underdamped and overdamped systems, is equal to 2*sqrt(m*k) = 2*sqrt(0.5*12.5) = 5 Ns/m.

Learn more about Damped Oscillations here:

https://brainly.com/question/29451479

#SPJ3

The expression "1in. = 2.54cm" is properly called: A. an equation B. a conversion factor C. a rule of thumb D. an equivalence statement

Answers

Answer:

B. a conversion factor

Explanation:

The expression "1 in. = 2.54 cm" is called a conversion factor.

With this expression inches can be converted to centimeters.

Inversely the expression can also be used to convert centimeters to inches

By rearranging the equation we get

[tex]\frac{1}{2.54}\ inches=1\ cm\\\Rightarrow 1\ cm=0.394\ inches[/tex]

The statement which shows the equal nature of two different expressions is called an equation

Rule of thumb is a general approximation of a result of a test or experiment.

Hi your answer is B on edge

A satellite of mass 5000 kg orbits the Earth (mass = 6.0 x 1024 kg) and has a period of 6000 s. In the above problem the altitude of the satellite above the Earth's surface is

Answers

Answer:

altitude of satellite from earth surface is 7140 km

Explanation:

given data:

mass of satellite = 5000kg

altitude of satellite from earth surface can be calculated by using given relation

[tex]p^2 = \frac{(4* \pi^2)(a^3)}{(G*M)}[/tex]

where,

p -  satellite's period in seconds,

a - satellite's altitude in meters,

G - gravitational constant (6.67 x 10^-11 m³/kgs²) and

M -  mass of Earth 5.98 x 10^24 kg

solving for altitude we have

[tex]a^3 =\fracp{(G*M*p^2)}{(4*\pi^2)}[/tex]

[tex]a^3 = 3.637 * 10^{20}[/tex]

a = 7,138,000 meters = 7,140 km

altitude of satellite from earth surface is 7140 km

Building helps children develope their _____ skills

A. number sense and operations

B. operations and geometry

C. measurement and counting

D. measurement and geometry

Answers

Answer:

D. measurement and geometry

Explanation:

Building helps children develop their _ measurement and geometry__ skills. The measurement and geometry skill of the children by observing buildings.

Geometry is a method or tool for understanding the relations among shapes and spatial properties. Children can develop spatial reasoning and can visualize shapes in different positions (orientation) when observing a building.

When a particular wave is vibrating with a frequency of 4.00 Hz, a transverse wave of wavelength 60 cm is produced. Determine the speed of waves along the wire.

Answers

Answer:

Speed of the wave, v = 2.4 m/s

Explanation:

Given that,

Frequency of vibrations, f = 4 Hz

Wavelength of the transverse wave, [tex]\lambda=60\ cm=0.6\ m[/tex]

We need to find the speed of the waves along the wire. Let it is equal to v. So, the relationship is given by :

[tex]v=f\times \lambda[/tex]

[tex]v=4\times 0.6[/tex]

v = 2.4 m/s

So, the speed of waves along the wire is 2.4 m/s. Hence, this is the required solution.

Final answer:

The speed of the transverse wave on the wire, given a frequency of 4.00 Hz and a wavelength of 60 cm, is calculated to be 2.40 meters per second (m/s) using the formula Speed = Frequency × Wavelength.

Explanation:

To determine the speed of a wave, you can use the formula:

Speed = Frequency × Wavelength

In the given scenario, the frequency is 4.00 Hz, and the wavelength is 60 cm, which is equivalent to 0.60 meters (since 1 meter = 100 cm). Thus, the speed of the wave on the wire can be calculated as follows:

Speed = 4.00 Hz × 0.60 m

Speed = 2.40 m/s

Therefore, the speed of the transverse wave along the wire is 2.40 meters per second (m/s).

A ball is tossed with enough speed straight up so that it is in the air serveral seconds. Assume upwards direction is positive and downward is negative. What is the change in its velocity during this 1-s interval?

Answers

Answer:

- 32.17 fts/s in the imperial system, -9.8 m/s in the SI

Explanation:

We know that acceleration its the derivative of velocity with respect to time, this is (in 1D):

[tex]a = \frac{dv}{dt}[/tex]

So, if we wanna know the change in velocity, we can take the integral:

[tex]v(t_f) - v(t_i) = \int\limits^{t_f}_{t_i} {\frac{dv}{dt} \, dt = \int\limits^{t_f}_{t_i} a \, dt[/tex]

Luckily for us, the acceleration in this problem is constant

[tex]a \ = \ - g[/tex]

the minus sign its necessary, as downward direction is negative. Now, for a interval of 1 second, we got:

[tex]t_f = t_i + 1 s[/tex]

[tex]v(t_i + 1 s) - v(t_i) =  \int\limits^{t_i + 1 s}_{t_i} a \, dt[/tex]

[tex]v(t_i + 1 s) - v(t_i) =  \int\limits^{t_i + 1 s}_{t_i} (-g ) \, dt[/tex]

[tex]v(t_i + 1 s) - v(t_i) =  [-g t]^{t_i + 1 s}_{t_i} [/tex]

[tex]v(t_i + 1 s) - v(t_i) =  -g (t_i+1s) + g t_i [/tex]

[tex]v(t_i + 1 s) - v(t_i) =  -g t_i + -g 1s + g t_i[/tex]

[tex]v(t_i + 1 s) - v(t_i) =  -g 1s [/tex]

taking g in the SI

[tex]g=9.8 \frac{m}{s^2}[/tex]

this is:

[tex]v(t_i + 1 s) - v(t_i) =  - 9.8 \frac{m}{s} [/tex]

or, in imperial units:

[tex]g=32.17 \frac{fts}{s^2}[/tex]

this is:

[tex]v(t_i + 1 s) - v(t_i) =  - 32.17 \frac{fts}{s} [/tex]

For two different inertial frames of reference would acceleration and change in velocity be different? How would energy be affected?

Answers

Answer and Explanation:

The inertial reference frame is one with constant velocity or non-accelerated frame of reference.

The value of acceleration and velocity change will vary in the two frames and will not be same.

As in case, we observe the acceleration and velocity of a moving train from the platform and the one observed in the train itself will be different.

In case of energy, it is dependent on the frame of reference but the energy change is independent of the frame of reference.

supply 5 N∙m of torque to a bolt located at the origin using a wrench that lies along the positive yy-axis. Assume the bolt head is at the origin and the threaded portion of the bolt lies along the negative xx-axis. If you apply a 25 N force at the end of the wrench in the direction 2???????? − 3????????, what length of wrench would be required to supply the desired torque? Under this force are we tightening or loosening the bolt?

Answers

Answer:

Explanation:

We need to supply 5 Nm to the bolt.

If we have a force of 25 N in the direction (2*i - 3*j), the torque is related to the length of the wrench.

T = F * d

d = T / F

d = 5 / 25 = 0.2 m

Assuming the wrench is perpendicular to the force.

The vector of the force is:

[tex]F = 25 N \frac{2i - 3j}{\sqrt{2^2 + (-3)^2}} = 13.9i - 20.8[/tex]

This is a countr-clockwise direction. If the bolt is right handed (most are) we are tightening it.

How many photons are emitted per second by a He−Ne laser that emits 1.5 mW of power at a wavelength λ=632.8nm. What is the frequency of the electromagnetic waves emitted by a He−Ne laser?

Answers

Answer:

The frequency of the emitted EM wave by He-Ne laser is [tex]4.74\times 10^{14} Hz[/tex]

Given:

Power emitted by He-Ne laser, P = 1.5 mW = [tex]1.5\times 10^{- 3}[/tex]

Wavelength, [tex]\lambda = 632.8 nm = 632.8\times 10^{- 9} m[/tex]

Solution:

Now, to calculate the frequency, [tex]\vartheta[/tex] of the EM wave emitted:

Energy associated with 1 photon = Power of one photon per sec = [tex]\frac{hc}{\lambda}[/tex]

Therefore, power associated with 'N' no. of photons, P = [tex]N\frac{hc}{\lambda}[/tex]

where

[tex]h = 6.626\times 10^{-34} m^{2}kg/s[/tex] = Planck's constant

Now,

[tex]1.5\times 10^{- 3} = N\frac{6.626\times 10^{-34}\times 3\times 10^{8})}{632.8\times 10^{- 9}}[/tex]

N = [tex]4.77\times 10^{15}[/tex]

Also, we know that:

[tex]c = \vartheta \lambda[/tex]

Thus

[tex]\vartheta = \frac{c}{\lambda} = \frac{3\times 10^{8}}{632.8\times 10^{- 9}}[/tex]

[tex]\vartheta = 4.74\times 10^{14} Hz[/tex]

Cheetahs can accelerate to a speed of 21.8 m/s in 2.55 s and can continue to accelerate to reach a top speed of 28.1 m/s . Assume the acceleration is constant until the top speed is reached and is zero thereafter. Let the +x direction point in the direction the cheetah runs. Express the cheetah's top speed vtop in miles per hour (mi/h) .
Starting from a crouched position, how much time totall does it take a cheetah to reach its top speed and what distance d does it travel in that time?
If a cheetah sees a rabbit 122.0 m away, how much time ttotal will it take to reach the rabbit, assuming the rabbit does not move and the cheetah starts from rest?

Answers

Answer:

Explanation:

Given

Cheetah  speed=21.8 m/s in 2.55 sec

i.e. its [tex]a=\frac{21.8}{2.55}=8.55 m/s^2[/tex]

Cheetah top speed=28.1 m/s

And 1 m/s is equal to 2.23694 mph

therefore 28.1 m/s is [tex]2.236\times 28.1=62.858 mph[/tex]

Time taken to reach top speed

v=u+at

[tex]28.1=0+8.55\times t[/tex]

[tex]t=\frac{28.1}{8.55}=3.286 s [/tex]

Distance traveled during this time

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

[tex]28.1^2=2\times 8.55\times s[/tex]

[tex]s=\frac{789.61}{2\times 8.55}=46.176 m[/tex]

If cheetah sees a rabbit 122 m away

time taken to reach rabbit

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

[tex]122=0+\frac{1}{2}\times 8.55\times t^2[/tex]

[tex]t^2=\frac{244}{8.55}[/tex]

[tex]t=\sqrt{28.53}=5.34 s[/tex]

A 280 g object is attached to a spring and executes simple harmonic motion with a period of 0.270 s. If the total energy of the system is 4.75 J. (a) Find the maximum speed of the object _______ m/s (b) Find the force constant of the spring_________ N/m (c) Find the amplitude of the motion_________m

Answers

Answer:

Explanation:

given,

mass of the object = 280 g = 0.28 kg

time period = 0.270 s

total energy of the system  = 4.75 J

                 [tex]\dfrac{1}{2}\ m\ V^2 = 4.75 J[/tex]

maximum speed of the object V =     [tex]\sqrt{ \dfrac{2 \times 4.75}{0.28} }[/tex]

                                              V= 5.82 m / s

(b)   force constant of the spring K = m ω²

where ω = angular frequency = 2π / T

          T= time period = 0.25 s

ω = 25.13 rad / s

K = 0.28 × 25.13²

K = 176.824 N / m

(c). Amplitude of motion A =    [tex]\dfrac{V}{\omega}[/tex]

                                         =     [tex]\dfrac{5.82}{25.13}[/tex]

A = 0.232 m

An aircraft is in a steady level turn at a flight speed of 200 ft/s and a turn rate about the local vertical of 5 deg/s. Thrust frm the engine is along the flight direction. Given the weight of the aircraft as 50,000 lb and L/D of 10, determine the lift, drag and thrust required for the given equilibrium flight. Assume g = 32.2 ft/s

Answers

Answer:

L =4166.66 N   and  D = 46296.29 N and T = 96047.34 N

Explanation:

given,

flight speed = 200 ft/s

turn rate = 5 deg/s

weight of aircraft = 50000 lb

L/D = 10

for equilibrium in the horizontal position

w - L cos ∅ - D sin ∅ = 0 .............(1)

D cos ∅ - L sin ∅ = 0................(2)

L/D = tan ∅ = 10

∅ = 84.29°

50000 - L cos  84.29°- D sin  84.29°= 0

D cos  84.29° - L sin 84.29° = 0

on solving the above equation we get

L =4166.66 N   and  D = 46296.29 N

thrust force calculation:

T = W sin ∅ + D

  = 50000×sin 84.29 + 46296.29

T = 96047.34 N

A special standard weight, known to weight 10 N to high accuracy, is used to check the accuracy of two spring scales. On the first scale the weight gives a reading of 8.4 N. On the second scale the weight gives a reading of 9.1 N. The percent difference between the measurements of the two scales is %. (Never negative.)

Answers

Answer:

16 % and 9 %

Explanation:

Accurate reading = 10 N

reading of first balance = 8.4 N

reading of second balance = 9.1 N

Percentage difference in first reading

= [tex]\frac{True reading - reading of first balance}{True reading}\times 100 %[/tex]

= [tex]\frac{10-8.4}{10}\times 100 %[/tex] = 16 %

Percentage difference in second reading

= [tex]\frac{True reading - reading of second balance}{True reading}\times 100 %[/tex]

= [tex]\frac{10-9.1}{10}\times 100 %[/tex] = 9 %

A 11400 kg lunar landing craft is about to touchdown on the
surface of the moon. acceleration due to gravity onmoon is 1.0
m/s2. At an altitude of 165 m the craft's downwardvelocity is 18.0
ms . To slow down the craft, a retrorocket isfired to provide an
upward thrust. Assuming the descent isvertical, find the magniturde
of the trhust needded to reduce thevelocity to zero at the instant
when the craft touches the lunarsurface.

Answers

Answer:

F = 22572N

Explanation:

We will first calculate the acceleration needed to achieve landing speed equals zero:

[tex]V_{f}^{2}=V_{o}^{2}+2*a*\Delta Y[/tex]

[tex]0=18^{2}+2*a*(-165)[/tex]   Solving for a:

[tex]a=0.98 m/s^{2}[/tex]

Now that we have the required acceleration, we need to check all forces acting on the craft:

[tex]F_{thrust} - W = m*a[/tex]   where W = 11400N; m = 11400Kg; a = 0.98m/s2

Solving the equation:

[tex]F_{thrust}=22572N[/tex]

Final answer:

The magniture of thrust required to reduce the lunar craft's velocity to zero can be calculated using the principles of kinematics and forces. The change in kinetic energy is calculated and equated with the work done by the retro-rocket's thrust, in order to find the required thrust.

Explanation:

The physics involved in this problem is related to kinematics and forces. To calculate the amount of thrust needed, we first need to find the change in kinetic energy. The initial kinetic energy is 0.5 * 11400 kg * (18 m/s)^2 and the final kinetic energy is zero since the craft is at rest. Therefore, the change in kinetic energy is -0.5 * 11400 kg * (18 m/s)^2.

By the work-energy theorem, the work done by the retro-rocket's thrust is equal to the change in kinetic energy. Since work done is also equal to force (thrust) multiplied by distance, we can equate these two expressions to find the thrust: Thrust * 165 m = -0.5 * 11400 kg * (18 m/s)^2. Solve for thrust to get the magnitude of thrust needed.

Learn more about Physics of Lunar Landing here:

https://brainly.com/question/5527401

#SPJ3

What is the net charge of a metal ball if there are 21,749 extra electrons in it?

Answers

Answer:

[tex]Q=3.47\times 10^{-15}\ C[/tex]

Explanation:

Given that,

Number of extra electrons, n = 21749

We need to find the net charge on the metal ball. Let Q is the net charge.

We know that the charge on an electron is [tex]q=1.6\times 10^{-19}\ C[/tex]

To find the net charge if there are n number of extra electrons is :

Q = n × q

[tex]Q=21749\times 1.6\times 10^{-19}\ C[/tex]

[tex]Q=3.47\times 10^{-15}\ C[/tex]

So, the net charge on the metal ball is [tex]3.47\times 10^{-15}\ C[/tex]. Hence, this is the required solution.

An observer is approaching at stationary source at 17.0 m/s. Assuming the speed of sound is 343 m/s, what is the frequency heard by the observer if the source emits a 2550-Hz sound?

Answers

Answer:

the frequency heard by the observer is equal to 2677 Hz

Explanation:

given,      

velocity of the observer = 17 m/s

speed of the sound = 343 m/s    

velocity of the source = 0 m/s    

frequency emitted from the source  = 2550 Hz              

[tex]f = f_0(\dfrac{v-v_0}{v-v_s})[/tex]              

[tex]f = 2550\times (\dfrac{343+17}{343-0})[/tex]

velocity of observer is negative as it is approaching the source.                   f = 2676.38 Hz ≈ 2677 Hz                    

hence, the frequency heard by the observer is equal to 2677 Hz

A car traveling 56.0 km/h is 25.0 m from a haystack when the driver slams on the brakes. The car hits the haystack 2.11 s later. How fast is the car traveling at impact?

Answers

Answer:

The car is traveling at [tex]8.1366\frac{m}{s}[/tex]

Explanation:

The known variables are the following:

[tex]V_{0} = 56 \frac{km}{h} = 15.56 \frac{m}{s}\\ D=25m\\ t=2.11s\\ V_{f}=?[/tex]

First, from the equation of motion we find the deceleration:

[tex]D=V_{0}*t+\frac{1}{2} a*t^{2} \\ a=\frac{2(D-V_{0})}{t^{2} } \\ a=3.5182\frac{m}{s^2}[/tex]

Then, with the equation for the speed:

[tex]V_{f}=V_{o}+a*t\\ V_{f}=8.1366\frac{m}{s}[/tex]

Final answer:

The speed of the car at impact is approximately 25.72 m/s.

Explanation:

To find the speed of the car at impact, we first need to calculate the deceleration. We can use the equation v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time taken.

Given that the initial velocity (u) is 56.0 km/h, the distance (s) is 25.0 m, and the time taken (t) is 2.11 s, we can rearrange the equation to solve for a: a = (v - u) / t.

Plugging in the values, we have a = (0 - 56.0 km/h) / 2.11 s = -26.5 m/s². Since the car is decelerating, the acceleration is negative.

Now, to find the final velocity (v) at impact, we can use the equation v² = u² + 2as. Rearranging the equation, we have v² = u² + 2(-26.5 m/s²)(25.0 m) = u² - 2(26.5 m/s²)(25.0 m).

Plugging in the values, we have v² = (56.0 km/h)² - 2(26.5 m/s²)(25.0 m).

Converting the initial velocity (u) to m/s, we get u = 56.0 km/h * (1000 m/1 km) * (1 h/3600 s) = 15.6 m/s.

Substituting the values, we have v² = (15.6 m/s)² - 2(26.5 m/s²)(25.0 m) = 0.16 m²/s² - 26.5 m²/s² * 25.0 m = 0.16 m²/s² - 662.5 m²/s² = -662.34 m²/s².

Taking the square root of both sides, we get v ≈ √(-662.34 m²/s²) ≈ -25.72 m/s.

Since speed is a positive quantity, the speed of the car at impact is approximately 25.72 m/s.

A race car travels 40 m/s around a banked (45° with the horizontal) circular (radius = 0.20 km) track. What is the magnitude of the resultant force on the 80-kg driver of this car? O a. 0.72 kN O b.0.68 kN O c. 0.64 kN O d.0.76 kN O e. 0.52 kN

Answers

Answer:

c)[tex]F_{net} = 0.640 kN[/tex]

Explanation:

As we know that resultant force is the net force that is acting on the system

As per Newton's II law we know that net force is product of mass and acceleration

so we will have

[tex]F_{net} = ma[/tex]

here we know

m = 80 kg

for circular motion acceleration is given as

[tex]a_c = \frac{v^2}{R}[/tex]

[tex]a_c = \frac{40^2}{200} = 8 m/s^2[/tex]

now we have

[tex]F_{net} = 80 \times 8[/tex]

[tex]F_{net} = 640 N[/tex]

[tex]F_{net} = 0.640 kN[/tex]

Other Questions
12. Which organelles are known as the "power plants"of the cell because they transfer chemical energyfrom food to compounds the cell can use?a. mitochondriab. ribosomesc. lysosomesd. vacuoles If my mass is 196 lbm and I tackle one of my teammates - while decelerating from a velocity of 6.7 m/s to 0 m/s in 0.5 s, how much force (kN) do I impart to the teammate's body? Wizard Co. purchased two machines for $250,000 each on January 2, 2005. The machines were put into use immediately. Machine A has a useful life of 5 years and can only be used in one research project. Machine B will be used for 2 years on a research and development project and then used by the production division for an additional 8 years. Wizard uses the straight-line method of depreciation. What amount should Wizard include in 2005 research and development expense? Why were kings in the late thirteenth and early fourteenth centuries able to control the church more than the church could control the kings? How did the kings attack the church during this period? Select the term used to describe the process, within the context of Active Directory, that allows a person with higher security privileges to assign authority to a person of lesser security privileges to perform certain tasks. a) Authority delegation b) Policy control c) OU control d) Delegation of control which is a family with nonmetals whose atoms gain or share one electron in chemical reactions The reason that there are Okazaki fragments during DNA replication is ultimately because:A) Some parts of the chromosome are made of RNA and different polymerases have to be usedB) Polymerases can only synthesize in the 5' to 3' directionC) There are only enough dNTP's to support quick replication on one strand, so the other strand lags behind itD) It is necessary to "slow down" one of the strands so that replication does not occur before cells have a chance to grow What is the meaning of this simile from "The Golden Cat"? a) The cat likes the sun because it is warm. b) The cat's claws are visible through the blinds, like small rays of light. c) The cat's claws are sharp. d) The cat enjoys sleeping in the sun. Please QUICK Would like assistance in understanding and solving this example on Elementary Number Theory with the steps of the solution to better understand, thanks.a) Let a = 123 and b = 76. Find (a,b) using the Euclidean algorithm. Then find x and y such that ax+by = (a,b).b) Show that 361x+2109y = 1000 does not have integer solutions. x+2y=-5y=x+2solve x and y 10 points i mark you as brainlist if you answer them At Phill's Discount Car Kingdom, you can purchase a used car for $14,000. Phill offers you two payment options: Option 1: You can apply an immediate cash rebate of $2,000 from the dealer to reduce the cost of the car and finance the rest with a loan that has an annual rate of 3.6%, with interest compounded monthly, for 3 years. You would make equal payments at the end of each month until the loan was repaid . Option 2: You can take out a 0% loan for the full price of the car in which you agree to pay the same amount at the end of each month for 3 years until the car is paid off What is the total amount that you would pay (out of pocket) for the car under each option? Reflect on the feedback you received from WriteToLearn about your persuasive essay. Which traits are strongest in your persuasive essay: ideas, organization, voice, word choice, sentence fluency, or conventions? Provide textual evidence from your essay to support your answer. Where did native Americans live and describe the area?? Berta wants to plant 1,224 trees in 8 equal rows. How many trees will go in each row? PLZ ANSWER I AM DOING A TEST.... :(Why did the United States cut off trade and diplomatic relations with Cuba?A. The revolutionary government had seized U.S. businesses and property in Cuba.B. Cuba had threatened to invade the United States.C. The United States was told to do so by the Soviets.D. A Cuban spy plane had been shot down over the United States. a store light flashes every 60 minutes while another light flashes open every 24 minutesif both stores begin flashing at 10 am what time will they both flash together again Help me please!! 30 points What is the product?(2x - 1)(x+4)2x?-42x+42x+7-42x? - 7x-4 Two parallel plates 19 cm on a side are given equal and opposite charges of magnitude 2.0 10^9 C. The plates are 1.8 mm apart. What is the electric field (in N/C) at the center of the region between the plates? (Enter the magnitude.)