A block of mass 0.1 kg is held against a

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A block of mass $0.1 \,kg$ is held against a wall by applying a horizontal force of $5\, N$ on the block. If the coefficient of friction between the block and the wall is $0.5$, the magnitude of the frictional force acting on the block is ........ $N$

A

$2.5$

B

$0.98 $

C

$4.9$

D

$0.49$

A block of mass $0.1 \,kg$ is held against a wall by applying a horizontal force of $5\, N$ on the block. If the coefficient of friction between the block and the wall is $0.5$, the magnitude of the frictional force acting on the block is ........ $N$

Limiting friction ${F_l} = {\mu _s}R = 0.5 \times (5) = 2.5\;N$

Since downward force is less than limiting friction therefore block is at rest so the static force of friction will work on it.

${F_s}$ $=$ downward force $=$ Weight

$ = 0.1 \times 9.8 = 0.98\,N$