Question

Assertion (A) It is always necessary that external agency of force is in contact with the object while applying force on object. Reason (R) A stone released from top of a building accelerates downward due to gravitational pull of the earth.

Assertion (A) At the microscopic level, all bodies are made of charged constituents (nuclei and electrons) and various contact forces arise. Reason (R) These forces are due to elasticity of bodies, molecular collisions and impacts, etc.