Test: Force and Laws of Motion- Assertion & Reason Type Questions - Class 9 MCQ

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion : Change in momentum is impulse.

Reason : Impulse is the area between (F-t) graph and time axis.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion: If a balanced force is applied on a wooden block it will move.

Reason: Unbalanced force changes the state of motion or rest while balanced force does not.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

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 motion.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion: A five rupee coin has more inertia than one rupee coin.

Reason: Inertia does not depend upon mass of the object.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion : Force exerted by the ground on the man moves him forward.

Reason : It is a reactional force.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion: Sudden application of brakes in a moving car may cause injury.

Reason: Inertia is the tendency of an object to keep moving or being at rest undisturbed.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion : A table cloth cannot be pulled from a table without dislodging the dishes.

Reason : Newton’s second law of motion gives definition of inertia

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion: Momentum of an object which is the product of mass and velocity is a vector quantity.

Reason: Momentum has both direction as well as magnitude.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion : When we sit on a chair, our body exerts a force downward and that chair needs to exert an equal force upward or the chair will collapse.

Reason : The third law says that for every action there is an equal and opposite reaction.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion : When astronauts throw something in space, that object would continue moving in the same direction and with the same speed.

Reason : The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion : A body is momentarily at rest when it reverses the direction.

Reason : A body cannot have acceleration if its velocity is zero at a given instant of time.

Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:

Assertion : From Newton’s second law of motion, impulse is equal to change in momentum.

Reason : Impulse and momentum have different SI units.