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Impulse and Momentum

You can know what is impulse and its applications by visiting this site. Impulse is the change in momentum that occurs when a force is applied to a moving or a stationary body. Newton’s second law of motion governs the relationship between the change on velocity and the force applied on a body. Impulse is created when a force is applied to an object. It is a product of force act in a certain direction and time.

Mathematical Expression of Impulse

Impulse=Ft
It is a vector quantity because force acts in a certain direction. Its SI unit is Newton-second (Ns). Impulse is one of the important qualities of physics. People use it when solving certain problems in physics. Physicians use both impulse and momentum to calculate collision problems. A good example of impulse is when a cue strikes the pool ball. Both the cue and the ball are in contact for a short period, a millisecond, but the result is observable. This quantity is directly related to momentum.

Impulse-Momentum Theorem

According to this theorem, Impulse is equal to the rate of change of momentum. Ft=(M(v-u))/t
F=M(v-u)
Ḟ Δt =m Δv, Where v and u are the final and initial velocities respectively. M is the mass of the object on which the force is applied. If the mass of the object is changing,
F dt= m dv + v dm, This is equivalent to the force of law, Newton’s second law of motion. The SI unit for momentum is kilogram meter per sec (Kg m/s).

Applications of Impulse

  • A vehicle can travel smoothly even when the road is uneven because its shock absorbers are capable of reducing force. This is done by increasing the time of impulse.
  • A person receives more injuries when he/she falls from a raised ground than falling on a heap of sawdust. This is because sawdust is capable of absorbing shock or impulse of force.
  • Cricket players have to lower their hands while catching the ball. It is by so doing that the impact of force is reduced. Increasing the time of impact is an effective way of decreasing the effect of force on the ball.
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