Q.

A block of mass 5 kg is moving on an inclined plane which makes an angle of 30with the horizontal. The coefficient of friction between the block and the inclined plane surface is 32 The force to be applied on the block so that the block will move down without acceleration is_______N.

(g=10 m/s2)         [2026]

1 12.5  
2 25  
3 7.5  
4 15  

Ans.

(1)

mgsin30°=F+μmgcos30°

F=5×10×12-32×5×10×32

F=25-752=25-37.5

F=-12.5 N

 Force will be downward on incline of magnitude 12.5 N