Pendulum Energy Conservation · PhysicsBowl 2007 #7
Physics · mechanics
Problem
A mass connected to a string swings back and forth as a pendulum with snapshots of the motion seen in the figure. Ignore the friction in the system. Which of the following statements about the pendulum-Earth system is correct?
[Figure: Pendulum positions labeled A, B, C, D, E showing swing motion]
(a) The total mechanical energy in the system is constant.
(b) The total mechanical energy in the system is maximum at B.
(c) The potential energies at A and C are equal.
(d) The kinetic energies at C and D are equal.
(e) The kinetic energy at E equals the kinetic energy at C.