1) What is the current through and voltage across a capacitor after it is fully charged in a DC circuit?

a) I=0, V=0

b) I=0, V=max

c) I=max, V=0

d) I=max, V=max

2) What is the current through and voltage across a capacitor after it is fully discharged?

a) I=0, V=0

b) I=0, V=max

c) I=max, V=0

d) I=max, V=max

An object with mass m = 0.6 kg is dropped from the top of the building and falls 21 m down in front of the cafe.

1.1 Calculate the speed of the object as it hits the ground and calculate the time for the fall. Neglect in this question the air resistance.

In a more accurate calculation we need to take air resistance into account. In a wind tunnel the air resistance of the object has been measured giving rise to an acceleration of: a_air = 0.03v² where v is the speed of the object.

1.2 Now, taking air resistance into account, find the speed of the object as it hits the ground. Any integrals in your calculation should be calculated by hand!

1.3 Calculate the time of the fall when air resistance is taken into account. (You are allowed to use calculator to calculate occurring integrals when answering this question!)

Consider the air tracks from lab: A car of mass m is set in motion with constant speed. As it moves down the track a mass of 2m is dropped onto the car without causing any damage. The car and additional load continue along the track. How does kinetic energy of the car + load compare to the original kinetic energy of the car?

1) The kinetic energy is 3 times the original kinetic energy

2) The kinetic energy is equal to the original kinetic energy    

3) The kinetic energy is 1/2 times the original kinetic energy

4) The kinetic energy is 1/3 times the original kinetic energy

5) The kinetic energy is 2 times the original kinetic energy

Question 54 1 pts What happens to a given mass of water as it is cooled from 4°C to zero? it contracts it expands it vaporizes none of the above Flag this Question Question 55 1 pts A gasoline engine operates between a high temperature TH = 127oC a low temperature TC = 27o C. If this engine operates with Carnot efficiency, its efficiency is closest to 10% 25% 33% 79%

In an EM wave traveling west, the B field oscillates up and down vertically and has a frequency of 91.0 kHz and an rms strength of 7.15×10−9T. Assume that the wave travels in free space.

Part A: What is the frequency of the electric field? Express your answer to three significant figures and include the appropriate units.

Part B: What is the rms strength of the electric field? Express your answer to three significant figures and include the appropriate units.

Part C: What is the direction of its oscillation?

To prevent dust and soot particles from polluting the atmosphere, industry often employs static electric charges in their smokestacks.

Explain the physics principle involved in this application.

2) The Plank radiation law is

I(lambda) = 2 pi h c²/[lambda⁵ (e ^{hc/labda kT} -1)]

take the derivative of this expression with respect to lambda to show

lambda_max = hc/(4.965kT).

You may uses 5 - x = 5 e^-x is true for x = 4.965.

The charge at a point in space is q (t) = 0.5 cos (6t) C. What is the current at t = −2 s? At an arbitrary time t?

A -10.0 nC point charge and a +20.0 nC point charge are 15.0 cm apart on the x-axis.

Part A)

What is the electric potential at the point on the x-axis where the electric field is zero? Answer in V

Part B)

What is the magnitude of the electric field at the point on the x-axis, between the charges, where the electric potential is zero? Answer in N/C

An object with total mass m_total = 14.6 kg is sitting at rest when it explodes into three pieces. One piece with mass m₁ = 4.7 kg moves up and to the left at an angle of θ₁ = 20° above the –x axis with a speed of v₁ = 26.8 m/s. A second piece with mass m₂ = 5.1 kg moves down and to the right an angle of θ₂ = 25° to the right of the -y axis at a speed of v₂ = 23.5 m/s.

What is the x-component of the velocity of the third piece?

What is the y-component of the velocity of the third piece?

What is the magnitude of the velocity of the center of mass of the pieces after the collision?

Calculate the increase in kinetic energy of the pieces during the explosion.

1. Derive PV^Gamma = constant

2. All adiabatic relations

An 8000 kg truck traveling with a velocity of 20. 0 m/s in a direction 30 ° south of east and a 6250 kg car traveling with a velocity of 25. 0 m/s 40 ° north of east collide in a perfectly inelastic collision. Find (a) the final speed and (b) the direction of the combined mass. Also, calculate (c) the change in the kinetic energy of the system.

1. Determine the variance in position and momentum, Δx²=<x²>−<x>² and Δp²=<p²>−<p>² for the ground-state SHO and show that they satisfy the Heisenberg uncertainty relation, (Δx)(Δp)≥ℏ2

Two cars are approaching each other, one traveling north with a momentum of 3 kg-m/s and one traveling east with a momentum of 4 kg-m/s. The two cars collide and stick together. Right after the collision (choose all that apply)

1. the eastern component of the momentum of the two cars is 4 kg-m/s.

2. the northern component of the momentum of the two cars is 3 kg-m/s.

3. the total momentum of the two cars is 7 kg-m/s