Find the value of friction forces between the blocks A and B and between B and ground. ( Take , `g=10 ms^(-2)`)

Options

A. 90 N,5 N
B. 5 N,90 N
C. 5 N,75 N
D. 0 N,80 N

Answer

D

Explanation

(d) Maximum force of friction between ground and B is `f=(M+m)mu g`
`implies (15+5)(0.6)(10)=120N`

As `f_("max")gtF`
`therefore` Frictional force between B and ground will be 80 N.