Laws Of Motion Question 330
Question: A block B is pushed momentarily along a horizontal surface with an initial velocity V. If p is the coefficient of sliding friction between Band the surface, block B will come to rest after a time
Options:
A) $ \frac{g\mu }{V} $
B) $ \frac{g}{V} $
C) $ \frac{V}{g} $
D) $ \frac{V}{g( \mu)} $
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Answer:
Correct Answer: D
Solution:
[d] Friction is the retarding force for the block
$ F=ma=\mu R=\mu mg $
Therefore, from the first equation of motion $ v=u-at $
$ 0=V-\mu g\times t\Rightarrow \frac{V}{\mu g}=t $