A horizontal force of `25 N` is necessary to just bold a block stationary against between the block and the wall is `0.4` The weight of the block is

Options

A. `2.5 N`
B. `20 N`
C. `10 N`
D. `5 N`

Answer

c

Explanation

Given horizontal force `F = 25 N` and coefficient of friction between block and wall `(mu) = 0.4`
we know thet at qeuilibrium horizontal force provides the normal reaction to the block against the wall Therefore normal reaction to the block `(R ) = F = 25 N`
we also know that weidge of the block `(w) =` frictional force `= mu R = 0.4 xx 25 = 10 N`