A hockey puck slides across nearly friction-free ice at after being struck
PHYSICS · Single correct · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics
Problem
A hockey puck slides across nearly friction-free ice at 8m/s after being struck. No horizontal forces act on the puck after it leaves the stick. Which statement best accounts for the puck’s nearly constant speed?
(a) Because no horizontal net force acts on the puck, its momentum—and therefore its speed—remains constant.
(b) The force from the stick is stored in the puck and continues to push it forward after contact, so its speed does not change.
(c) The ice supplies a forward force that exactly balances air resistance, keeping the puck moving at the same speed.
(d) An object's own mass makes it resist slowing down, so the puck’s mass keeps it moving at 8m/s.