A block the of mass `4kg` is placed on another block of mass `5kg` and the block `B` rests on a smooth horizontal table for sliding the block `A` on `B` a horizontal force `12N` is required to be applied force on it How much maximum horizontal force can be applied on 'B' s that both `A` and `B` move together? Also find out the accleration proudced by this force
.

Options

A. 30 N
B. 25 N
C. 27 N
D. 48 N

Answer

C

Explanation

Minimum force on A
= frictinoal force between the surfaces =12 N
Therefore maximum acceleration
`a_("max")=(2N)/(4kg)=3m//s^(2)`
Hence maximum force,
`F_("max")="total mass" xx a_("max")`
`=9xx3=27N`