A lift accelerates upward with a=g. A block of mass m is released from the top of a smooth wedge of equal mass m, height h and angle θ. The time to reach the bottom is:

Question

G1 Physics · Accepted Answer

In the lift frame effective gravity is 2g. Solving the coupled smooth-wedge dynamics gives relative acceleration 4g sinθ/(1+sin²θ). Using path length h/sinθ and s=(1/2)at² gives the stated time.