The product of average force and the time it is exerted is called the impulse of force. From Newton's second law [pic]
the impulse of force can be extracted and found to be equal to the change in momentum of an object provided the mass is constant: |[pic] |Calculation |
The main utility of the concept is in the study of the average impact force during collisions. For collisions, the mass and change in velocity are often readily measured, but the force during the collision is not. If the time of collision can be measured, then the average force of impact can be calculated.
Examples Involving Impulsive Force
• Playing football
• Playing badminton
• Playing tennis
• Playing golf
• Playing baseball
Impulsive force is produced during collision according to the Newton's Second Law. If time of impact is reduced, the greater the impulsive force produced causing severe damage to the car.
1. The long jump pit is filled with sand to increase the reaction time when atlete land on it. 2. This is to reduce the impulsive force acts on the leg of the atlete because impulsive force is inversely proportional to the reaction time. High Jump
• During a high jump, a high jumper will land on a thick, soft mattress after the jump. • This is to increase the reaction time and hence reduces the impulsive force acting on the high jumper. Jumping
A jumper bends his/her leg during landing. This is to increase the reaction time and hence reduce the impact of impulsive force acting on the leg of the jumper. Crumble Zone
The crumple zone increases the reaction time of collision during an accident. This causes the impulsive force to be reduced and hence reduces the risk of injuries.
Prevent the driver and passengers from being flung forward or thrown out of the car during an emergency break.