A `2 kg` block is present against a rough wall by a force `F = 20 N` as shown in figure .Find acceleration of the block and force of friction acting on it .`(Take g = 10 m//s^(2))`

Explanation

`N = 20 N=` applied force
`mu_(s) N = 16 N`
and `mu_(k) N = 12 N`
Driving force `F = mg` (downward)
Since `F gt mu_(k) N`, block will slide downwards and kinetic frictioin of `12 N` will act in upward direction `:. a=(F - mu_(k) N)/(m)` (downward)
`= (20 - 12)/(2) = 4 m//s^(2)` (downward)