Q55 / 270 · NDA 2021 (Phase 1) · General Ability

The statement "friction force is a contact force while magnetic force is a non-contact force" is

  • Correct answer
    A
    always true.
  • B
    true only at $0^{\circ} \mathrm{C}$.
  • C
    a false statement.
  • D
    either true or false depending upon the temperature of the surroundings.

Solution

Magnetic forces are non- contact forces; they pull or push on objects without touching them. Magnets are only attracted to a few 'magnetic' metals and not all matter. Magnets are attracted to and repel other magnet. Non-contact force occurs due to either attraction or repulsion between two objects such that there is no contact between these objects. There is no field linked with the contact force. There is always a field linked with non-contact force. - Friction is a contact force when two surfaces interact. The static friction case is similar for when the two surfaces are stationary relative to each other. In static friction, the frictional force is whatever value it needs to be to prevent sliding up to some maximum value.

Hence, the correct answer is option: 'A'.

Relevant Questions