Suppose a 10 kg ball makes a one dimensional collision with a 5 kg ball. Think about what could happen to the velocity of the 5 kg ball as a result of the collision. Could it remain unchanged? Could it increase? Could it decrease? Is it possible for both balls to end up traveling in the same direction after the collision? For each result you think could happen, please briefly explain why and offer an example of starting conditions that would cause that result. If you think a certain result couldn't happen, please also briefly explain why.

A  green laser operates at 488.0 nm with an output power of 2.5 mW. Calculate the average output in photons/s (“photon flux”). What would the output power be for the same flux of 244.0 nm photons? What would the photon flux be for a 488.0 nm laser operating at 5.0 mW?

A charge of -5.50nC is spread uniformly over the surface of one face of a nonconducting disk of radius 1.00cm

Part A

Find the magnitude of the electric field this disk produces at a point P on the axis of the disk a distance of 3.00cm from its center.

Part B

Suppose that the charge were all pushed away from the center and distributed uniformly on the outer rim of the disk. Find the magnitude of the electric field at point P.

Part C

If the charge is all brought to the center of the disk, find the magnitude and direction of the electric field at point P.

Part D

Why is the field in part (a) stronger than the field in part (b)?

Part E

Why is the field in part (c) the strongest of the three fields?

A 4 kg block is placed at the top of an inclined plane. The plane is 2.5 meters long and inclined at 34°. The coefficient of kinetic friction between the block and plane is 0.27. The block slides the 2.0 meters down the ramp. What speed does it have at the bottom?

What is the relationship between the index of refraction and the density of the transparent material? Is this relationship a rule of thumb or is it an absolute?

Water flows through the pipe in the figure below and exits to the atmosphere at the right end of section C. The diameter of the pipe is 2.12 cm at A, 4.24 cm at B, and 0.880 cm at C. The gauge pressure in the pipe at the center of section A is 1.25 atm and the flow rate is 0.856 L/s. The vertical pipes are open to the air. Find the level (above the flow midline as shown) of the liquid-air interfaces in the two vertical pipes. Assume laminar nonviscous flow.
h_A = m

h_B = m

In the series RLC circuit of problem 1 the resistor is replaced with the higher available value of 68 KOhm. The circuit is driven in forced oscillation regime up to a frequency of 200 KHz. A resonance is observed at a frequency of the order of 160 KHz. How would you explain this result? What combinations of capacitor / inductor values would produce a resonance at that frequency, and what parts of the setup are possible candidates for effective reactance elements at that frequency?

Explain the mathematical and graphical relationship between velocity and position using your own words.

A mole of atoms is 6.02 x 10^23 atoms. To the nearest order of magnitude, how many moles of atoms are in a 8 kg domestic cat? The masses of a hydrogen atom, an oxygen atom, and a carbon atom are 1.0 u, 16 u, and 12 u, respectively. (Hint: Cats are sometimes known to kill a mole.)

Acceleration of Gravity

1) Friction. Explain the role of friction in the measurement of g.

2) Time. The time resolution of the timer used in the experiment is 0.1 ms (milliseconds). Do you expect that the precision of the timer may have affected the measurement of g?

3) Distance. How do you expect that the measurement of the distance D between the photogates may have affected the measurement of g?

4) Angle. How do you expect that the measurement of the angle of incline θ may have affected the measurement of g?

5) Summary. Based on the % difference histogram, which of the possible causes listed above do you think did actually affect the measurement of g? If so, in which direction?

Most string theory compactifications analyzed so far have as backgrounds a conformal field theory corresponding to a nonlinear sigma model with a Calabi-Yau target space, or some relatively classical background, possibly with orbifolding. But as long as the central charge of the Virasoro algebra is right, and worldsheet superconformal symmetry is respected, any other superconformal field theory will do just as well. Why haven't string theorists looked at such models more often?

A parallel plate capacitor with plate separation d is connected to a battery. The capacitor is fully charged to Q Coulombs and a voltage of V. (C is the capacitance and U is the stored energy.) Answer the following questions regarding the capacitor charged by a battery.

For each statement below, select True or False. and please explain answers Thanks!

1) With the capacitor connected to the battery, decreasing d increases U

2) After being disconnected from the battery, inserting a dielectric with ? will decrease V

3) After being disconnected from the battery, decreasing d increases C

4) With the capacitor connected to the battery, inserting a dielectric with a dielectric constant "k" will decrease C

5) After being disconnected from the battery, increasing d decreases V

6) With the capacitor connected to the battery, inserting a dielectric with a dielectric constant "k" will decrease U

An energy bill on the floor of the House of Representatives is proposed by a congressperson from Nebraska that would require all cars to use fuel that contains at least 15% ethanol, derived from corn. A northeastern state representative raises the concerns that corn is best for cattle, food, and exports, and that not all cars of today are prepared to use such a fuel. Respond how you would vote on this issue and the reasoning behind your vote in a 100-word essay