An optical interferometer can detect a displacement of 0.1?, or ?50nm.

At what speed would a 3.0m stick "shrink" by 50 nm? Hint: Use the binomial approximation.

8.0 x 10^15 electrons flow through a cross section of silver wire in 340 us with a drift speed of 7.6 x 10^-4m/s .

What is the diameter of the wire?

Please answer it well.

TRUE or False: Beyound the point of stall, the wing generates zero lift and the airplane falls from the sky.

An electron collides elastically with a stationary hydrogen atom. The mass of the hydrogen atom is 1837 times that of the electron. Assume that all motion, before and after the collision, occurs along the same straight line. What is the ratio of the kinetic energy of the hydrogen atom after the collision to that of the electron before the collision?

Sketch a PV diagram and find the work done by the gas during the following stages. (Draw the PV diagram on paper. Your instructor may ask you to turn in this work.)

(a) A gas is expanded from a volume of 1.0 L to 2.6 L at a constant pressure of 3.1 atm.
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(b) The gas is then cooled at constant volume until the pressure falls to 1.8 atm.
J

(c) The gas is then compressed at a constant pressure of 1.8 atm from a volume of 2.6 L to 1.0 L. [Note: Be careful of the signs.]
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(d) The gas is heated until its pressure increases from 1.8 atm to 3.1 atm at a constant volume.
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(e) Find the net work done during the complete cycle.
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1. The primary of a step-up transformer connected to a 120 V source has 200 turns. If the output is 480 V, how many turns does the secondary have?

2. The primary of a step-down transformer connected to a 240 V source has 1500 turns. The secondary has 200 turns.   What is the output voltage of this transformer?

3. A laptop computer requires 24 volts to operate properly. A transformer with 600 turns in the primary needs to have how many turns in the secondary to operate the computer from a 120 V source?

4. If the output current for the transformer in the previous problem is 4.5 A, calculate the input current.

5. A transformer has an input of 24 V and an output of 36 V. If the input is changed to 12 V what will the output be?

6. A model electric train requires 12 V to operate. When connected to a household voltage of 120 V, a transformer is needed. If the primary coil has 250 turns, how many turns must the secondary coil have?

7. A transformer has 25 turns in the primary coil and 200 turns in the secondary coil. If 24 V is connected to the primary coil and a 20-Ω device is connected to the secondary coil, calculate the current in Amperes passing through the device.

8. Neon signs need 12,000 V to operate. If a transformer operates off a 240 V source and has 1000 turns in its primary coil, how may turns must the secondary coil have?

9. A power of 200 kW is delivered by power lines with 48,000 V difference between them. Calculate the current, in amps, in these lines.

10. If the lines in problem #9 above, have a resistance of 100-Ω, calculate the change of voltage along each line.

Your group has the following equipment: An electroscope, a foam tube, fur, a small plastic cup, a small metal cup. You perform the experiments described below and record the outcomes. For each of the experiments, use your understanding of the electric field to explain why each outcome happened.

-Make sure your explanations use the concept of the electric field rather than “opposite charges attract/same charges repel” ideas.

-Draw LARGE charge diagrams to illustrate your explanations. Show the shape of the electric field by including electric field lines.

Experiments:

a. Bring the charged end of a foam tube down toward the top of an uncharged electroscope without touching the electroscope. Outcome: The metal strips separate.

b. Take the charged end of the foam rod away from the top of the uncharged electroscope. Outcome: The metal strips come back together

c. Repeat the first two experiments, only this time a metal can covers the electroscope but doesn’t touch it. Outcome: The metal strips do not separate.

d. Repeat the first two experiments, only this time a glass beaker covers the electroscope but doesn’t touch it. Outcome: The metal strips separate then come back together, but much less significantly than in experiments a. and b.

Kepler-1625b is the name of a planet found outside our solar system. Its mass is 3180x larger than Earth and its radius is 9x larger than Earth
(a) What is the gravitational acceleration (little g) on the surface of this planet?
(b) This planet may have a moon. If it has the same mass of Earth what is the gravitational force between the planet and moon? If the moon orbits 400,000 km away how fast does it orbit?

A 0.550 kg metal cylinder is placed inside the top of a plastic tube, the lower end of which is sealed off by an adjustable plunger, and comes to rest some distance above the plunger. The plastic tube has an inner radius of 7.41 mm, and is frictionless. Neither the plunger nor the metal cylinder allow any air to flow around them. If the plunger is suddenly pushed upwards, increasing the pressure between the plunger and the metal cylinder by a factor of 2.55, what is the initial acceleration of the metal cylinder? Assume the pressure outside of the tube is 1.00 atm.

1. Based on the centripetal force law, explain why specific speed limit sign is posted on the banked curves of the roads

2. Is it more difficult to do a sit-up with your hands stretched in front of you or with them behind your head? Explain.

3. When would a ball hitting a wall have a greater change in momentum: when it hits the wall and bounces back at the same speed or when it hits and sticks to the wall? Explain.

A ladder of length 2L and mass M is positioned on level ground leaning against a wall such

that the angle between the ladder and the horizontal is α. The coefficient of static friction

between the ladder and the wall and between the ladder and the ground is μstatic = 0.65. The

centre of mass of the ladder is halfway along it.

(b) Draw a diagram indicating all the forces acting on the ladder, and state what each force

represents. Also show the direction of the x- and y-axes you will use. (Hint: there are 2

forces acting at the top of the ladder, 2 forces acting on the bottom of the ladder and 1 force

acting at its centre.)

(c) For the ladder to be in mechanical equilibrium:

(i) Write down equations for the total x- and y-components of the 5 forces acting on the

ladder.

(ii) Consider torques about the centre of the ladder. In which direction (into or out of the

page) does the torque due to each of the 5 forces force act?

(iii) Write down an equation for the sum of the torques about the centre of mass of the

ladder.

(iv) Use your equation for the torques to derive an expression for tan α in terms of the

magnitudes of the forces acting.

(d)(i) If the ladder is just on the point of slipping at both the upper and lower ends, what

can you say about the pair of forces acting at each of the top and bottom of the ladder?

(ii) Hence use this information, with the information from (c)(i) and the expression you have

derived in (c)(iv) to calculate the minimum angle that the ladder can form with the ground

in order for it not to slip. (Hint : In the expression for tan α, you will need to write each of

the forces in terms of one of the normal reaction forces, which then cancel out, leaving an

expression for tan α in terms of μstatic only.)

Please answer and provide explanation on how to solve these problems. Thank you!

1) A block of mass 5.67 kg rests on a horizontal table. The block is pushed with a force of 70.2N that makes an angles of 25.0 degrees with the horizontal. The coefficient of kinetic friction between the block and surface of the table is 0.256. What is the acceleration of the block? What is its speed after traveling 2.30m?

2) The volume and the pressure of the Argon gas of 2.00 mol are 2.000L and 10.0atm respectively. The molar mass of Argon is 40.00 g/mol. Wha id the vrms speed of argon atom?

Compare this with vrms speed of hydrogen under the same conditions! Molar mass of hydrogen is 2,00g/mol.

1 atm = 10^5 Pa; 1L = 10^-3 m^3. R = 8.314 J/mol.k

3)A 250.0 g of copper calorimeter contain 500.0g of water at 20.0C. A block of mass 100.0g at 25.00C of water at 85.00C are added to the calorimeter. When thermal equilibrium is reached the final temperature of the system is 50.00C. What is the specific heat of the block?

Specific heat: Copper = 387J/kg.C; Water = 4186J/Kg.C

4) A container is filled up to the rim with 1.5L of mercury at 20C. he container is heated to 70C, 8ml of mercury spills out. Calculate the linear expansion coefficient of the container. The volume expansion of mercury is 1.8x10^-4/C. 1L = 10^-3 m^3, 1ml = 10^-3 L

if the nested solenoids were used as a step up transformer which coil would you connect the time varying current to? what is your predicted value of the ratio of the voltages?

if the nested solenoids were used as a step down transformer which coil would you connect the time varying current to? what is your predicted value of the ratio of the voltages?

Two loudspeakers emit sound waves along the x-axis. A listener in front of both speakers hears a maximum sound intensity when speaker 2 is at the origin and speaker 1 is at x = 0.450 m . If speaker 1 is slowly moved forward, the sound intensity decreases and then increases, reaching another maximum when speaker 1 is at x = 0.850 m.

A.What is the frequency of the sound? Assume v_sound =340m/s.

B. What is the phase difference between the speakers?

A mass of 1.62 kg stretches a vertical spring 0.318 m. If the spring is stretched an additional 0.137 m and released, how long does it take to reach the (new) equilibrium position again? ______s