Question

Mark is applying a large force inorder to push a heavy cupboard lying on the floor. Then his brother Tony spreads a little bit of oil on the floor. Now, Mark feels that it has become relatively easier to move the cupboard. Why?

• A. Oil magnifies the applied muscular force
• B. Oil reduces the friction between two surfaces
• C. Application of oil generates an upward thrust
• D. Application of oil reduces the gravitational force

Answer 1

The correct option is B Oil reduces the friction between two surfaces

Usage of lubricants helps to reduce friction between the moving surfaces. Oil is one of the best lubricants. Since friction always opposes motion, the resistance against the motion of the cupboard is reduced on the oil spread floor. Hence, Mark could push the cupboard by applying a relatively lesser force.