Question

Block A of mass 2kg is placed over a block B of mass 8kg. The combination is placed on a rough horizontal surface. If g = $10m{s}^{-2}$, coefficient of friction between B and floor = 0.5, coefficient of friction between A and B = 0.4 and a horizontal force of 10 N is applied on 8kg block, then the force of friction between A and B is

• A. 100 N
• B. 50 N
• C. 40 N
• D. zero

Answer 1

The correct option is D zero

$f_{2max}=\mu N_2=0.5x10g$
= 50 N
Since applied force = 10N
The system does not move