10. Conservation of Energy

Which of the following statements about the energy of a pendulum is true?

At equilibrium in a pendulum, the potential energy is $0$ and the velocity is ________.

When a roller coaster car moves down from the top of a hill, which of the following best describes the energy transformation that occurs in the system?

In a system where a particle moves along a frictionless track and its potential energy as a function of position is shown in the graph below, at which point on the graph does the particle have its maximum kinetic energy?

Three identical carts, $A$, $B$, and $C$, are connected by light strings and pulled together over a frictionless track. As the system passes over the top of a bump, which cart has the greatest speed at the top of the bump?

Which of the following best describes how the energy in ocean waves can be transformed into electrical energy in a connected system?

When $E$ (energy) is transferred into a container holding marbles, how does this affect the speed ($v$) of the marbles inside the system?

Two masses are connected by a string as shown in Fig. 8–35. Mass m_A = 3.5 kg rests on a frictionless inclined plane, while m_B = 5.0 kg is initially held at a height of h = 0.75 m above the floor. Use conservation of energy to find the velocity of the masses just before m_B hits the floor. You should get the same answer as in part (b).

The 9.0-kg mass in Fig. 8–36 is held just barely in contact with a spring for which k = 450 N/m . When that mass is released, it falls, compressing the spring and pulling the 3.0-kg mass up. How far does the 9.0-kg mass fall before momentarily coming to rest? Ignore friction in the pulley.