Question

Decrease of which one of the following quantities enables us to transport even a heavy

barrel by rolling across the road?

(a) Weight.(b)Normal friction

(c)Limiting friction.(d)Coefficient of fric​

Answer 1

• .(d)Coefficient of friction...

Answer 2

(d)Coefficient of friction, enables us to transport even a heavy barrel by rolling across the road.

Explanation:

• To make a body comes in motion we apply force, if the body is heavy it become difficult to roll the body due to frictional force acting backwards in the wheels of the body.

    when the body is in rest,just before the motion

•        f =μN (μ is the friction coefficient and N is the normal reaction that any surface apply on a body,as per newton's 3rd law of motion.)

•       N=mg(mg is the weight , force acting downwards.)
•       f= μmg =F ,here we see that we have to minimise the value of friction coefficient to make the heavy body in motion