Two blocks of masses `8kg` and `6kg` are connected with a string `&` placed on a rough horizontal surface. Surface itself is accelerating up with constant acceleration `2m//s^(2)`. Two forces `60 N` each are acting on the two blocks as shown. Friction coefficient for `8kg` is `0.5 &` that for `6 kg` is `0.6.` Tension in the string is : `(g=10m//s^(2))`

Options

A. 60 N
B. 12 N
C. 43.2 N
D. 16.8 N

Answer

D

Explanation

`f_(R)` for `8kg = 0.5 xx 8(10+2)=48 N`
`f_(R)`f or `6kg xx 6(10+2) = 43.2 N`
It can be verified that limiting friction will act on 6kg
From FBD tension = 16.8 N