Question
A block B is pushed momentarily along a horizontal surface with an initial velocity v. if μ is the coefficient of sliding friction between B and the surface, block B will come to rest after a time:
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v/gμ
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gμ/v
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g/v
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v/g
Solution
A.
v/gμ
Block B will come to rest, if force applied to it will vanish due to frictional force acting between block B and surface, ie,
force applied = frictional force
i.e., μmg = ma
μmg = m (v/t)
t =v/μg
