Numerical Problems Based on Class 11 Physics Linear Momentum and Force

Home » CBSE Class 11 Physics » Extra Questions for Class 11 Physics » Numerical Problems Based on Class 11 Physics Linear Momentum and Force

Momentum

Momentum of a body is the quantity of motion possessed by the body. It is equal to the product of mass and velocity of the body.

Momentum = Mass × velocity = mv

Momentum is a vector quantity because the velocity  is a vector and mass m is a scalar. Its direction is same as the direction of the velocity of the body. Its magnitude is given by

p = m v

SI unit of momentum = kg ms-1

CGS unit of momentum = g cm s-1.

The dimensional formula of momentum is [MLT-1].

Newton’s Second Law of Motion:

The rate of change of linear momentum of a body is directly proportional to the applied force and the change takes place in the direction of the applied force.

F = dp/dt

Numerical Problems Based on Class 11 Physics Linear Momentum and Force

Q.1. A truck starts from rest and rolls down a hill with constant acceleration. It travels a distance of 400 m in 20 s. Calculate the acceleration and the force acting on it if its mass is 7 metric tonnes.

Show Answer Answer: 2 ms-2,14,000 N

Q.2. A balloon has a mass of 5 g in air. The air escapes from the balloon at a uniform rate with a velocity of 5 cms-1. If the balloon shrinks completely in 2.5 s, find the average force acting on the balloon.

Show Answer Answer: 10 dyne

Q.3. A motor car running at the rate of 7 ms-1 can be stopped by applying brakes in 10 m. Show that total resistance to the motion, when brakes are on, is one fourth of the weight of the car.

Show Answer Answer:

Q.4. A force acts for 10 s on a body of mass 10 kg after which the force ceases and the body describes 50 m in the next 5 s. Find the magnitude of the force.

Show Answer Answer: 10 N

Q.5. A force of 50 N is inclined to the vertical at an angle of 30°. Find the acceleration it produces in a body of mass 2 kg which moves in the horizontal direction.

Show Answer Answer: 12.5 ms-2

Leave a Reply

Download Updated White Label Product Brochures (2023-24) 

%d bloggers like this:
search previous next tag category expand menu location phone mail time cart zoom edit close