Question

A body of mass 2 kg resting on a horizontal surface is acted upon by a horizontal force of
magnitude 20N. If coefficient of kinetic friction is 0.4 and static friction 0.5, then
magnitude of frictional force acting on the body will be....(g=10ms ?)
1) 8N
2) 10 N
3) 20 N
4) 2.5 N​

Answer 1

Solution :-

As per the given data ,

• Mass of the body (m)= 2 kg
• Force acting upon the body (F) = 20 N
• Coefficient of kinetic friction (μk)=  0.4
• Coefficient of static friction (μs)=  0.5

First let us find the value of limiting friction acting on the body

we know that ,

➝ F(lim) = μsN

➝ F(lim) = μs mg

➝ F(lim) = 0.5 x 2 x 10

➝ F(lim) = 10 N

As the limiting friction is less than the force applied the block will move

Hence ,

The magnitude of frictional force acting on the body is 10 N