Newton's Second Law of Motion

Author:V K Sally & R Goel
9th CBSE
IMPORTANT

Important Questions on Newton's Second Law of Motion

MEDIUM
IMPORTANT

Derive the unit of force using the second law of motion. A force of 5 N produces an acceleration of 8 ms-2 on a mass m1 and an acceleration of 24 ms-2 on a mass m2. What acceleration would the same force provide if both stones are tied together?

MEDIUM
IMPORTANT

What is momentum? Write its SI unit. Interpret force in terms of momentum? Represent the following graphically.

(a) Momentum versus velocity when mass is fixed.

(b) Momentum versus mass when velocity is constant.

HARD
IMPORTANT

Using second law of motion, derive the relation between force and acceleration. A bullet of 10 g strikes a sand-bag at a speed of 103 ms-1 and gets embedded after travelling 5 cm. Calculate 
(i) the resistance force exerted by the sand on the bullet. 
(ii) the time taken by the bullet to come to rest.

MEDIUM
IMPORTANT

A car initially at rest, picks up a velocity of 72 km/h in 20 seconds. If the mass of the car is 1000 kg, calculate: (i) the force developed by its engine, and (ii) the distance covered by the car in 20 seconds.

MEDIUM
IMPORTANT

A force of  500 N acts on a body of mass x and gives it an acceleration of 200 m s-2. The same force acting on another body of mass y  gives it an acceleration of 40 m s-2. If x and  y are tied together and the same force as above, acts on them, what acceleration is produced in the combination?

EASY
IMPORTANT

A force of 100 N gives a body of mass m1, an acceleration of 5 m/s2. The same force can give an acceleration of 40 m/s2 to another body of mass m2. If both the bodies are tied together and acted upon by the same force as above, what acceleration is produced in the combination?

EASY
IMPORTANT

Two blocks of different metals, but identical in shape and size, are acted upon by equal forces, such that the acceleration of the second block is 3 times more than that of the first block. What is the ratio of the mass of the second block with respect to that of the first block?

EASY
IMPORTANT

A cyclist and a person on a moped are acted upon by the same force. If the acceleration produced by the cyclist is only 25th that of the moped, calculate the ratio of the masses of the cyclist and the moped.

EASY
IMPORTANT

The engine of a truck of mass 4 ton, produces a force of 7500 N. Calculate the acceleration of the truck produced by the engine.

EASY
IMPORTANT

Calculate the mass of a body, when a force of 525 N, produces an acceleration of 3.5 m/s2?

EASY
IMPORTANT

What force will produce an acceleration of 3.5 m/s2, in a body of mass 12.5 kg?                
 

MEDIUM
IMPORTANT

A truck of mass M is moved under a force F. If the truck is then loaded with an object equal to the mass of the truck and the driving force is halved, then how does the acceleration change ?

MEDIUM
IMPORTANT

Velocity versus time graph of a ball of mass 50 g rolling on a concrete floor is shown in figure. Calculate the acceleration and frictional force of the floor on the ball.

Question Image

MEDIUM
IMPORTANT

Prove mathematically: F=ma, where F is the force impressed on a body, 'm' the mass and 'a' the acceleration.

EASY
IMPORTANT

Define Newton’s second law of motion:

EASY
IMPORTANT

 A force F produces an acceleration a in a body. The same force produces an acceleration 4a in another body. The mass of the other body is:

EASY
IMPORTANT

Force remaining constant, if the mass of body increases, its acceleration is likely to:

EASY
IMPORTANT

A force of magnitude F acts on a body of mass m. The acceleration of the body depends upon :

EASY
IMPORTANT

A force of magnitude F acts on a body of mass m. The acceleration of the body depends upon :