If, in Q.19, coefficient of friction between m_(1) and the wall is mu,and f_(1) and f_(2) are respectively, the force of friction on m_(1) and m_(2), then :

If, in Q.19, coefficient of friction between m_(1) and the wall is mu,

1.	If, in Q.19, coefficient of friction between m_(1) and the wall is mu,and f_(1) and f_(2) are respectively, the force of friction on m_(1) and m_(2), then :
Answer» `f_(1)` and `f_(2)` both are downward. `f_(1)` and `f_(2)` both are downward. `f_(1)` is UPWARD and `f_(2)` upward. `f_(1)` is downward and `f_(2)` upward. Solution :In upward DIRECTION .