A Cart Loaded with Sand Slides Forward Along a Horizontal

Multiple Choice

A cart loaded with sand slides forward along a horizontal frictionless track.As the cart moves, sand trickles out at a constant rate through a hole in the back of the cart.The acceleration of the cart is:

A) constant and in the forward direction
B) constant and in the backward direction
C) variable and in the forward direction
D) variable and in the backward direction
E) zero