Two blocks A and B each of mass m are placed on a smooth horizontal surface. Two horizontal force F and 2F are applied on blocks A and B, respectively, as shown in fig. Block A does not slide on block B. Then then the normal reaction acting between the two blocks is (assume no friction between the blocks)

Options

A. F
B. `(F)/(2)`
C. `(F)/(sqrt(3))`
D. 3F

Answer

D

Explanation

(d) `a=(2F-F)/(2m)=(F)/(2m)`( toward left)
Writing equation of right hand side block,
`2F-N sin 30^(@)=ma=(F)/(2)`
`(N)/(2)=2F-(F)/(2)=(3F)/(2) implies N=3F`