Laws of Motion ...

Assertion Mass is a measure of inertia of the body in linear motion.
Reason Greater the mass, greater is the force required to change its state of rest or of uniform motion.

Assertion The slope of momentum versus time curve give us the acceleration.
Reason Acceleration is given by the rate of change of momentum.

Assertion A cyclist always bends inwards while negotiating a curve.
Reason By bending, cyclist lowers his centre of gravity.

Assertion The work done in bringing a body down from the top to the base along a frictionless incline plane is the same as the work done in bringing in down the vertical side.
Reason The gravitational force on the body along the inclined plane is the same as that along the vertical side.

Assertion Linear momentum of a body changes even when it is moving uniformly in a circle.
Reason Force required to move a body uniformly along a straight line is zero.

Assertion A bullet is fired from a rifle. If the riffle recoils freely, the kinetic energy of rifle is more than that of the bullet.
Reason In the case of rifle bullet system the law of conservation of momentum violates.

Assertion A reference frame attached to earth is an inertial frame of reference.
Reason The reference frame which has zero acceleration is called a non inertial frame of reference.

Assertion The apparent weight of a body in an elevator moving with some downward acceleration is less then the actual weight of body.
Reason The part of the weight is spent in producing downward acceleration, when body is in elevator.

Assertion When the lift moves with uniform velocity the man in the lift will feel weightlessness.
Reason In downward accelerated motion of lift, apparent weight of a body decreases.

Assertion Newton\'s third law of motion is applicable only when bodies are in motion.
Reason Newton\'s third law applies to all types of forces, e. g. , gravitational, electric or magnetic forces etc.