I was doing a past paper and this was the question: Use ideas about momentum to explain how this airbag can reduce injuries to pedestrians.
My answer: momentum is always conserved so momentum before the collision will equal the momentum after the collision. The airbag increases the time of impact and therefore the rate of change in momentum will be slower, this reduces the force on the pedestrians since force= change in momentum/ time taken. Since momentum remains the same, and the time is longer then the force will be reduced which will reduce the injury on the pedestrians.
Here is what the mark scheme said: MP1 momentum reduced;
MP2 by same amount;
MP3 over longer time;
MP4 so force reduced;
MP5 use of “force = rate of change of momentum”;
ignore “momentum absorbed”
MP6 less force means less damage/injuries;
Since i don't go to school at the moment i am finding it hard on how to mark my exam papers, so i was wondering if they will still give me marks even tho i don't have the exact same words??
Physics igcse Edexcel question watch
- Thread Starter
- 01-06-2016 11:15