A Large Spring Is Used to Stop the Cars After $\frac { 1 } { 2 }$

Multiple Choice

A large spring is used to stop the cars after they come down the last hill of a roller coaster.The cars start at rest at the top of the hill and are caught by a mechanism at the instant their velocities at the bottom are zero.Compare the compression of the spring,x_A,for a fully loaded car with that,x_B,for a lightly loaded car when m_A = 2m_B.

A) x_A = $\frac { 1 } { 2 }$ x_B.
B) x_A = x_B.
C) x_A = $\sqrt { 2 }$ x_B.
D) x_A = 2 x_B.
E) x_A = 4 x_B.