A body of mass 2

mass of the body m= 2kg

Angle of inclination θ = 30^°

Coefficient of static friction μ = 0.2

Case1: The diagram shown below represents the situation when block is moving up on the inclined plane.

…………………(i)

……………………(ii)

Using these two equations

Putting this value in equation (i), we get,

F= 13.5 N

Case 2: The diagram shown below represents the situation when block is moving down on the inclined plane

…………………(i)

……………………(ii)

Again, using these two equations,

Putting this value in equation (i), we get,

F= 2(9.8) ()- 0.2 (

F= 6.5 N

Due to this force, the body will move down the inclined plane with acceleration. Hence, no external force is required.