- Car Crash Victim
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Objectives:
- To be able to explain crashes and explosions in terms of momentum
Timing: 1-2 lessons
Last year you looked at the Physics of car safety features. This year you are going to look at the Physics of car crashes!
If you stand on a skateboard or sit on a chair with wheels and push against a wall, what happens? Why? What forces are acting on an object resting on a table?
Find out what momentum is. What units is it measured in? How is it calculated and what formula links force, time and change in momentum? http://www.antonine-education.co.uk/Physics_GCSE/Unit_2/Topic_4/topic__4.htm may help you.
Now think back to how crumple zones, seat belts and airbags reduce injuries. Look at the formula you've just written down and explain how these safety features work, in terms of the force exerted on the people in the car in the event of a crash.
Give some other everyday examples of collisions.
Momentum is always conserved i.e. momentum before a crash or explosion is the same as the momentum after. If you're lucky, Miss Hall will show you a piccie of her firing an AK47 assault rifle! It was very scary! You need to be able to explain why she ended up with a very bruised shoulder! You should also be able to explain how rockets are launched, in terms of momentum.
Your teacher will probably demonstrate some collisions using the linear air track.
Go to: http://spaceplace.nasa.gov/en/kids/funphysics.shtml and have a go at making a Newton's cradle to show the conservation of momentum.
You could do the following worksheets:
