NEET2019PhysicsLaws of MotionActual
A body of mass m is kept on a rough horizontal surface (coefficient of friction = ). Horizontal force is applied on the body, but it does not move. The resultant of normal reaction and the frictional force acting on the object is given F , where F is
Options
- A| F |=m g+ m g
- B| F |= m g
- C| F | m g 1+ ^2
- D| F |=m g
Correct answer
C. | F | m g 1+ ^2
Step-by-step solution
The situation can be drawn as The frictional force, f = N = mg [ N = mg ] From Free body diagram (FBD), the resultant force is aligned |F| & = N ^2+ f ^2 & = ( mg )^2+( mg )^2 = mg 1+ ^2 aligned This is the minimum force required to move the object. But as the body is not moving | F | mg 1- ^2