Question

Which of the following is not a contact force?

• A. Tension force
• B. Normal force
• C. Air resistance
• D. None

Answer 1

The correct option is D None

• Tension force applied by a rope on a body needs physical contact to pull the body.
• Normal force acts between two surfaces in contact. If two surfaces are not in contact, they can't exert a normal force on each other.
• Air resistance is the force in opposition to the relative motion of an object as it passes through the air. Here also, the air particles in contact with the surface of the object rub against it to slow it down.

All these forces are called as contact forces.

Hence, option D is correct.