Questions
A small conducting spherical shell with inner radius a and outer radius b is concentric with...

A small conducting spherical shell with inner radius a and outer radius b is concentric with a larger conducting spherical shell with inner radius c and outer radius d. The inner shell has a total charge of -1q and the outer shell has a total charge of +3q.

Select True or False for the following statements.

1. The total charge on the inner surface of the small shell is -4q.

2. The total charge on the outer surface of the small shell is zero.

3. The total charge on the inner surface of the large shell is +1q.

4. The radial component of the electric field in the region c < r < d is given by +3q/(4πε0r2).

5. The total charge on the outer surface of the large shell is +2q.

6. The radial component of the electric field in the region r > d is given by +2q/(4πε0r2).

7. The radial component of the electric field in the region r < a is given by +2q/(4πε0r2).

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An electric field given by E → = 5.5 i ̂ - 3.5(y2 + 4.6) j...

An electric field given by
E
= 5.5
i
̂
- 3.5(y2 + 4.6)
j
̂
pierces the Gaussian cube of edge length 0.250 m and positioned as shown in the figure. (The magnitude E is in newtons per coulomb and the position x is in meters.) What is the electric flux through the (a) top face, (b) bottom face, (c) left face, and (d) back face? (e) What is the net electric flux through the cube?



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Explain and demonstrate the use of a transistor hybrid model and frequency response for various amps....

Explain and demonstrate the use of a transistor hybrid model and frequency response for various amps. The demonstration must include a scenario where you show how Zin, Zout, av, ai and cutoff frequencies are calculated in:

CE scenario

CC scenario

CB scenario

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a) What is true about how atoms are bound together in a solid? b) What is...

a) What is true about how atoms are bound together in a solid?

b) What is mass density?

c) What is weight density?

d) What is volume?

e) What is surface area?

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1. A cyclist travels 500m in 35 seconds. During the 35 seconds the cyclist accelerates at...

1. A cyclist travels 500m in 35 seconds. During the 35 seconds the cyclist accelerates at a constant rate of 0.6 m / s2. Determine your initial speed.

2. A train travels at 14.0 m / s. The train accelerates at a rate of 1.2 m / s2. Determine its speed within 2.5 s.

3. An object is thrown horizontally at a speed of 12.5 m / s and a height of 14.0 m. Determine the time it takes you to hit the ground.

4. An object is pushed with a force of 10.0 and at an angle of -30.00, determine the vertical component of the force.

5. A ball is thrown directly downward at a speed of 5.0 m / s. It takes the ball 1.3 seconds to hit the ground. Determine the height at which it was launched.

6. A ball is thrown directly upward at a speed of 10.0 m / s. Determine the maximum height reached by the ball.

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From simple, visible observations (without the use of high-tech, modern technology) how do we know the...

From simple, visible observations (without the use of high-tech, modern technology) how do we know the Sun is rotating? What if the Sun stopped rotating? What about the Sun would be different; if anything at all? Is it important to our lives here on Earth or the future of the solar system that the Sun does continue to rotate? For this last set of questions, do not just answer an opinion here...actually do some research (internet if you wish) and describe at least ONE thing that would result if our Sun stopped rotating

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There is an experiment that demonstrates the first law of thermodynamics by using a tin can....

There is an experiment that demonstrates the first law of thermodynamics by using a tin can. The problem is I don't understand why there is a work done. The link to that video is https://youtu.be/jNPUCmkKiE4?list=WL&t=180 . Can someone explain to me why the tin can suddenly imploded?

In: Physics

What determines how light bends? Use the words: index refraction, incident angle, reflected angle, refracted angle,...

What determines how light bends? Use the words: index refraction, incident angle, reflected angle, refracted angle, and color.

In: Physics

ASTRONOMY (please type the answer not write ) Describe Jupiter – be careful and thorough. The...

ASTRONOMY (please type the answer not write )

Describe Jupiter – be careful and thorough. The length of your description should be equivalent of one single-spaced typed page.

In: Physics

A physics book slides off of a horizontal tabletop with a speed of 3.10 m/s. It...

A physics book slides off of a horizontal tabletop with a speed of 3.10 m/s. It strikes the floor in 0.500s. Ignore air resistance
A. find the height of the laptop
B. find the horizontal distance from the edge of the C. table to the point where the book strikes the floor
D. Find the horizontal component of the book's velocity, just before the book rewaches the floor
D. Find the vertical component of the book's velocity just before the book reaches the floor
E. find the magnitude of book's velocity, just before the book reaches the floor
F. Find the direction of the book's velocity , just before the book reaches the floor

In: Physics

In no more than one page, describe the Bohr model of the atom, the assumptions is...

In no more than one page, describe the Bohr model of the atom, the assumptions is it based on, and how it relates to the characteristic emission spectra from discharge tubes containing atoms such as sodium neon. You may include diagrams.

In: Physics

The New Horizons mission has continued to explore the solar system. When was New Horizons launched?...

The New Horizons mission has continued to explore the solar system. When was New Horizons launched? Where is New Horizons now? Describe at least two discoveries that New Horizons has made so far.

In: Physics

Try the following: get some stuff: a small ball (or some kind of object that will...

Try the following:

  • get some stuff:
    • a small ball (or some kind of object that will roll - a golf ball or marble or toy car is great, but an empty soup can will do in a pinch)
    • get a tape measure (a yardstick or a ruler will also work. You can also stretch a piece of string and mark off ruler lengths on the string to get the total length.)
    • around ten coins
  • Measure the distance from a tabletop or kitchen countertop down to the floor. Record the height in meters. (If you measured the height in inches then convert to meters by dividing the height by 39.36)
  • Calculate the time it would take any object to fall from the edge of the tabletop to the floor. Use the y-direction displacement formula: y = vyot + 1/2 ay t2 where
    • y = the height you measured DOWN to the ground
    • vyo = the initial vertical velocity - should be zero since an object that rolls off the tabletop will not initially be moving up or down, but only sideways
    • ay = the acceleration of gravity DOWN = 9.8 m/s2)
    • t = the time

Your Answer:Question 1 options:

Answer

Question 2 (1 point)

Try the following:

  • place the small ball on the tabletop, a foot or so from the edge
  • get one of the coins
  • give the ball a small push so that it rolls off the edge of the table and place the coin about where the ball lands on the floor
  • Roll the ball off the tabletop again, this time giving a more forceful push so the ball has more horizontal velocity and again mark its landing spot with a coin
  • repeat pushing the ball off the table and marking its landing position several times, each time with a little more force so as to give the ball a higher horizontal velocity when it leaves the tabletop

What is true of each recorded fall? MARK ALL THAT APPLY!

Question 2 options:

A)

No matter how fast the ball leaves the table horizontally, it still takes the same amount of time to fall from the tabletop to the floor

B)

Even when the ball leaves the tabletop with a higher horizontal velocity it always travels the same distance in the x-direction

C)

When the ball leaves the tabletop with a higher horizontal velocity it travels farther in the x-direction

Question 3 (1 point)

Try the following:

  • gather all the coins off the floor
  • On top of the table, make a small ramp out of a thin board or a magazine. Have the bottom edge of the ramp directly on the table about a foot from the edge. Use a couple books to support the top of the ramp closer to the middle of the table
  • Place a ball at the top of the ramp and allow it to roll down the ramp, across the foot of tabletop to the edge and go over the edge. Mark where the ball lands with a coin
  • Without changing the angle or position of the ramp, repeatedly release the ball from the top of the ramp and mark each landing spot with a coin

What is true of each recorded fall? MARK ALL THAT APPLY!

Question 3 options:

A)

If all factors could be perfectly controlled the ball would hit in the same spot everytime

B)

The landing spots are pretty uniform and the coins are very closely grouped on the floor.

C)

Everytime a ball rolls off the table, the table itself gets a little bit taller

Question 4 (1 point)

  • Go to https://phet.colorado.edu/sims/html/projectile-motion/latest/projectile-motion_en.html
  • Click the first square that reads "Intro"
  • You should see a cannon

Just to make sure you're in the right place, what color is the cannon?

Question 4 options:

A)

blue and yellow

B)

red and blue

C)

shades of gray

D)

red and yellow

Question 5 (1 point)

With all the original default settings (height = 10 m, angle = 0 degrees, vo = 15 m/s), press the red "Fire" button to shoot the cannon. There are three ways to measure the distance the projectile travels in the x-direction. any of the following will work:

  • click and drag the red and white target on the ground over to the landing spot so that the center of the target is at the end of the trajectory
  • click and drag the tape measure from the toolbox in the top right of the screen. Place the flat leading edge of the tape measure box on the ground directly below the "+" of the cannon and drag the end of the tape to the impact spot
  • click and drag the blue time/range/height tool from the toolbox in the top right of the screen. Place the crosshairs over the impact spot and a small yellow dot should appear. This is probably the best tool, since you can also read the time the projectile spent in the air and the range and the height above the ground.

Which of the following is closest to the actual distance the projectile travels in the x-direction?

Question 5 options:

A)

23.8 m

B)

21.4 m

C)

19.2 m

D)

15.0 m

Question 6 (1 point)

  • Find the time that it takes a stone to fall 13 m by using the y-displacement formula.
  • Set the cannon at 13 m and fire horizontally and use the blue time/range/height gauge to fine the time

How much time does it take to fall 13 m?

Question 6 options:

A)

15.96 s

B)

5.8 s

C)

1.63 s

D)

0.90 s

Question 7 (1 point)

If a cannon shoots a ball horizontally at 8 m/s, and the ball starts out 11 m above the floor, how far away from the gun will the ball land?

  • Solve the formula using the y-displacement formula to find the time and the x-displacement formula to find the range
  • Sent the cannon height at 11m and the initial speed at 8 m/s. Use the blue time/range/height gauge to find the range

What is the horizontal distance the projectile travels?

Question 7 options:

A)

5.2 m

B)

12 m

C)

2.67 m

D)

15 m

Question 8 (1 point)

Predict the horizontal distance a cannon on a 15 m cliff will shoot if it's horizontal initial velocity is 140 m/s .

Question 8 options:

A)

207 m

B)

245 m

C)

1052 m

D)

1089 m

Angle Shot

When the cannon is not horizontal, but is aimed either upwards or downwards, several additional considerations have to be made.

  • we have to find the x and y components of the inital velocity
    • vox = vo cos θ
    • voy = vo sin θ
  • we have to get the signs of the y components of velocity and acceleration and displacement correct. If the gun is angled up and gravity pulls down and the displacement is down. You can pick the y-coordinate sysytem either positive up/negative down OR positive down/negative up. It makes no difference which way you pick, but once you pick everything has to conform to that coordinate system. If we arbitrarily pick positive up
    • the upward initial velocity, voy would be up, so it would be a positive number
    • the gravity, ay pulls down, so it would be a negative number
    • the rock falls down, so the vertical displacement, y points down, so it would be a negative number
  • When we use the y-displacement formula to find time, since voy is no longer zero, as it was in the horizontal shot, we can't cancel the first right hand term. That means we have to solve the quadratic. Typically using the quadratic formula is the best choice for doing that. The quadratic formula gives two possible solutions - choose the one that makes sense (the positive answer)

For example: A cannonball leaves a cannon at 15 m/s from 10 m above ground, fired at an upward 30 degree angle. Find the time to hit the ground and the horizontal range.

Step 1: Y-direction to find Time Step 2: X-direction to find Range
  • voy = vo sin θ = 15 sin 30 = 7.5 (positive since aimed UP)
  • ay = -9.8 m/s^2 (negative since pulls DOWN)
  • y = -15 m (negative since DOWN)
  • t = the time we're looking for

y = voy t + 1/2 ayt2

-15 = 7.5 t + 1/2 (-9.8) t2

0 = -4.9 t2 + 7.5 t+15

Get the coefficients for the quadratic formula

a = -4.9 , b = 7.5 , c = 15

t = (-b ± √(b2 - 4 a c)) / (2 a )

t = (-7.5 ± √(7.52 - 4(-4.9)(15))) / (2 (-4.9))

t = -1.14s OR 2.67 s

  • vox = vo cos θ = 15 cos 30 = 13
  • ax = 0 (gravity doesn't pull sideways, no air resistance)
  • t = whatever we got from Step 1 = 2.67 s
  • x = the range we're looking for

x = vox t + 1/2 axt2

x = (13 m/s)(2.67 s) + 1/2 (0) (2.67)2

x = 34.8 m

Question 9

Set up the cannon so that

  • the height is 10 m
  • initial speed is 15 m/s
  • the angle is 0 degrees, horizontal
  • fire the cannon!

Tilt the barrel upwards to 30 degrees and FIRE!

Now, tilt the barrel downwards to 30 degrees and - 3, 2, 1 - FIRE!!!

You should see all three paths that the projectile took. You might need the blue measuring device, but MARK ALL THE APPLY THINGS:

Question 9

A)

When you tilt the gun higher, the shot spends less time in the air

B)

More angle = more time

C)

More time = more range

D)

Since the initial velocity and the height is the same for all three shots, the time in the air is the same.

Question 10

A cannonball leaves a cannon at 7 m/s from 4 m above ground, fired at an upward 25 degree angle. Find the time to hit the ground.

Do this by solving the quadratic and by shooting the virtual cannon

Your Answer:

Question 11

A cannonball leaves a cannon at 15 m/s from 5 m above ground, fired at an upward 30 degree angle. Find the horizontal diistance the shot travels.

Do this by solving the quadratic and by shooting the virtual cannon to compare.

Your Answer:

In: Physics

a) Two charges are close together. One charge has +9.6 C and the other has -3.2...

a) Two charges are close together. One charge has +9.6 C and the other has -3.2 C. If you were viewing a field line diagram of these charges what would you expect for the ratio of the number of lines extending to infinity divided by the number of lines that terminate on the negative charge?

b) You are sitting next to a positively charged metal sphere. What is the flux through the skin of your body due to the electric field of the sphere?

In: Physics

The VASIMR Rocket NASA plans to use a new type of rocket, a Variable Specific Impulse...

The VASIMR Rocket NASA plans to use a new type of rocket, a Variable Specific Impulse Magnetoplasma Rocket (VASIMR ), on future missions. If a VASIMR can produce 6.0 N of thrust (force), and has a mass of 620 kg, (a) what acceleration will it experience? Assume that the only force acting on the rocket is its own thrust, and that the mass of the rocket is constant. (b) Over what distance must the rocket accelerate from rest to achieve a speed of 9500 m/s?. (c) When the rocket has covered one-quarter the acceleration distance found in part (b), is its average speed 1/2, 1/3 or 1/4 its average speed during the final three-quarters of the acceleration distance? Explain.

In: Physics