Question

a body of 10 kg is kept on a rough horizontal surface which can offer maximum frictional force or 40 N what will be the frictional force when applied force is 20 N​

Answer 1

Explanation:

In horizontal direction, two forces are acting on the block : 100 N force and friction force (f)

f=μN=μmg=0.5×10×10=50N

So, net force acting on the block in horizontal direction = 100 N-50 N = 50 N

acceleration of the block = Net force / mass of block = 50 N/10 kg = 5 ms  

−2

Answer 2

Given :

The mass of the body = 10 kg

The maximum frictional force offered = 40 N

To find :

The value of frictional force when applied force is 20 N .

Solution :

Frictional force opposes the force applied on the body but it has some limitations .

It can opposes force equal to its maximum limit by applying equal and opposite frictional force .

When the applied force is 20 N , the frictional force is 20 N .