00:01
Hi, in this question we have a car having mass m given as 1 .5 into 10 race to par 3 kg and in a crash test this car collides with a wall and rebounds.
00:16
So the initial and final velocities of this car are given as vi equals to 15 meter per second and vr equals to minus 2 .6 meters.
00:30
Per second.
00:32
So if the collision lasts for time t equals to 0 .15 seconds, then in part a of this question we have to find the impulse that is delivered to the car due to the collision.
00:48
So impulse delivered can be calculated using formula ic equals to m delta v so this will be equals to mass m that is 1 .5 into 10 raised to power 3 into delta v that is change in velocity so that will be minus 2 .6 minus 15 so on solving this we get the value of i c equals to minus 2 .64 into 10 raised to power 4 kg meter per second so this is the impulse that is delivered to the now moving on to the next part, part b.
01:33
So in part b we have to calculate the magnitude of average force exerted on the car.
01:41
So we know that impulse that is ic is equals to f delta t where f is the force and t is the time period.
01:53
So f will be equals to ic by delta t.
01:57
So it will be minus 2 .64 into 10 raised 2 .5 divided by time that is 0 .15 which gives the value of force f equals to minus 1 .76 into 10 raised 2 power 5 newton and this force is against the motion of car.
02:29
Now, moving on to the last part, part c of this question.
02:37
So in part c of this question, we have to calculate that if the car doesn't rebound of the wall, but the collision time remains the same, what is the average force that is exerted on the car? so now, if the car does not rebound, then the final velocity, that is vr, will be zero...