Impulse equals change of momentum; useful for impacts.
Linear momentum p=mv; impulse J=∫F dt=Δp. A longer impact time reduces average force, explaining airbags and crumple zones. Momentum is conserved for a system with no external impulse.
A 0.15 kg ball changing speed by 40 m/s in 5 ms experiences 1200 N average force.
Impulse and momentum handle short, large forces such as impacts, where the force history is hard to know but its integral is easy to measure.
Impulse equals change of momentum; useful for impacts.
Impulse and momentum handle short, large forces such as impacts, where the force history is hard to know but its integral is easy to measure.
A longer contact time reduces the average force for the same change in momentum, because impulse is the force times the time.
Momentum is mass times velocity. Impulse is the change in momentum, equal to the time integral of the force.
Typical applications include estimating the average force of a golf ball hitting a club, designing a bumper that absorbs the momentum of a moving cart and computing the thrust from a rocket that expels mass at speed.
Study "Power" first (topic 30 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Vector quantity. Impulse = area under F-t graph. Rocket thrust follows from momentum change.
A 0.15 kg ball changing speed by 40 m/s in 5 ms experiences 1200 N average force.
The next topic is "Collisions", which builds directly on this one.
It is classed as Beginner in Engineering Mechanics (topic 31 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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