A pair of parallel plates, forming a capacitor, are charged. The plates are pulled apart to triple the original separation, the charges on the plates remaining the same. What is the ratio of the final energy stored to the original energy stored?
a. 1/9
c. 1/3
b. 1.5
d. 3
Question 2
A bucket of water with total mass 23 kg is attached to a rope, which in turn is wound around a 0.050-m radius cylinder at the top of a well. The bucket is raised to the top of the well and released. The bucket is moving with a speed of 6.0 m/s upon hitting the water surface in the well. What is the angular speed of the cylinder at this instant?
a. 39 rad/s
c. 120 rad/s
b. 79 rad/s
d. 160 rad/s
