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A wooden block of mass 100 Kg is kept on...

A wooden block of mass 100 Kg is kept on a horizontal platform. A force of 60 N is required to just slide the block. But a force of 49N is just sufficient to keep the block.moving with uniform velocity. What is the coefficient of kinetic friction?

A

0.5

B

0.25

C

0.05

D

0.005

Text Solution

Verified by Experts

The correct Answer is:
C

When the block is moving, we consider the kinetic friction. The coefficient of kinetic friction `mu_K=(F_K)/R`
In this case, `F_K=49N,R=mg=100xx9.8=980N`
`:." "mu_K=(49)/(980)=1/(20)=0.05`
`[mu_K`has no unit]
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Knowledge Check

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