Physics-
General
Easy
Question
A plank having mass M is placed on smooth horizontal surface. Block of mass m is placed on it coefficient of friction between block and plank is 
, where k is constant and x is relative displacement between block and plank. A force F is applied on block where F = at, where a = 10; t is in second. Find t0 when relative motion will occur between block and plank
The correct answer is:
Let at time t0 relative motion will occur
(1)
(2)
From (1) and (2) ;
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