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A long plank begins to move at t = 0 and...

A long plank begins to move at t = 0 and accelerates along a straight track with a speed given by `v= 2t^(2) " for" 0 le t le 2 .` After 2 s the plank continues to move at the constant speed acquired . A small block intially at rest on the plank begins to slip at t=1 s and stops sliding at t = 3 s. Find the coefficient of static and kinetic friction between the blck and the plank.

Text Solution

Verified by Experts

The correct Answer is:
7
`mu_(s)g= (dv)/(dt)` at `t=1` sec
`:. mu_(s)=0.4`
At `t=3` sec velocities of plank and block are equal.
`:.2+mu_(k)g(2)=v` at `t=3` sec `=8`
`:.mu_(k)=0.3`
`:.s+k=4+3=7`
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