I'm posting this on behalf of someone. Its for GCSE physics.
the question is
Lots of work has been done to increase the safety of roads.
This has included advances in crash barriers. Use ideas about forces and energy to explain how theses advances help road safety.
I already know that crash barriers work like crumple zones. I used large plastic water barrels to answer this question (crash barriers found in America) and said that they basically absorb the energy to gush the water upwards. However I need to answer it a bit more scientifically as the question says use ideas about forces and energy to explain you answer.
So can someone tell me how crash barriers or even water barrels work scientifically please?
Thank you, this will be much appreciated
Help with physics question watch
- Thread Starter
- 30-03-2011 14:13
- 30-03-2011 14:21
Start from the idea that work done by a force = force x distance moved (in the direction of the force).
If you want to stop a car moving at high speed you need to get rid of its kinetic energy.
You get rid of its kinetic energy by doing work on it.
In a crash, it's the barrier that does the work.