Question

Which of the following materials is likely to have least friction?
(A) Wood
(B) Plastic
(C) Glass
(D) Paper

Answer 1

Hint: Friction is a force that resists the sliding or rolling of one object over another or in other words we can say that it is an opposing force but it is not a fundamental force like gravity or electromagnet. If the surface is more rough then it will highly oppose the movement of the object.

Complete answer:
Friction opposes the motion of an object, causing moving objects to lose energy and slow down. When an object moves through a fluid such as air or water, the fluid exerts a friction force on the moving object similarly in case of solid it exerts an opposing force.
The friction can be reduced by polishing the surface as polishing makes the surface smooth and friction will be reduced.
If a material is rough, it will have more friction. Hence in the given options the materials which have a more polished and smoother surface will produce less friction on its surface. And we can see that glass has a comparatively better polished and smoother surface as compared to other materials present in the options i.e., wood, plastic and paper.
Therefore, Glass has less friction compared to other materials given in the options. So, option (C) is correct.

Note:
> Observe that wood produces more friction as compared to other materials present in options as it has a more rough surface.
> To reduce most of the machines use lubricant as friction produces heat which demamae the machine.
> If we walk on wet soil, we will slip due to less friction force between the ground and the body.