Solved Examples on Impulse
Example 1: An item comes to a halt when it collides with a solid wall. Calculate the object’s impulse if the object was 2.0 kg in weight and travelled at a speed of 10 m/s before colliding with the wall.
Solution:
Given,
Mass of the object, m = 2.0 kg
Initial velocity of the ball, vi = 10 m/s
Final velocity of the ball, vf = 0 m/s
The formula for impulse is:
J = m × (vf − vi)
Substitute all the values in the above equation.
J = 2 × (0 – 10) kg m/s
= -20 kg m/s
Hence, the impulse on the object is -20 kg m/s.
Example 2: A golfer hits a ball of mass 100 g at a speed of 50 m/s. The golf club is in contact with the ball for 2 ms. Compute the average force applied by the club on the ball.
Solution:
Given,
Change in the velocity, Δv = 50 m/s
Mass of the ball, m = 100 g = 0.1 kg
Time of contact, t = 2 ms = 0.002 s
The formula of impulse is:
J = F × Δt = m × Δv
F = m × Δv / Δt
Substitute all the values in the above equation.
F = (0.1) × (50) / 0.002 N
= 2500 N
Hence, the average force applied on the ball is 2500 N.
Example 3: Calculate the impulse on a body hit by a force of 500 N with a time of contact equal to 0.1s.
Solution:
Given,
Force exerted on body, F = 500 N
Time of contact, Δt = 0.1 s
Formula for impulse is,
J = F × Δt
=(500) × (0.1) N s
= 50 N s
Hence, the impulse on body is 50 N s.
What is Impulse?
Impulse in Physics is defined as the force acting on the body for a very shorter period of time. It is the instant change in the momentum of the body. For example, in case of collision, the instant change in the momentum of the body just before and after the collision is called the Impulse acting on the body.
The damage sustained by the body is dependent on the impulse applied to the body. It is denoted using the letter ‘J’ and is calculated by taking the product of the force applied and the time for which the force is applied.
In this article, we will discuss the concept of Impulse, its formula, equations, and others in detail in this article.