Forces Cause Changes in Momentum Flashcards
What does a force do when it acts on an object?
It causes a change in momentum
What is the formula relating time, force and change in momentum?
Force = change in momentum / time
What is Force measured in?
N (Newton’s)
What is change in momentum measured in?
Kg m/s
What is time measured in?
s (seconds)
What does a larger force mean?
A faster change of momentum
What happens if someone’s momentum changes very quickly?
The forces on the body will be very large, and more likely to cause injury
Why are cars designed to slow people down over a longer time when they crash?
The longer it takes for a change in momentum, the smaller the force
What do crumple zones do?
Crumple on impact, increasing the time taken for the car to stop
What do seat belts do?
Stretch slightly, increasing the time taken for the wearer to stop, reducing the forces acting on the chest
What do air bags do?
Slow you down more gradually
