A student investigates the effect of a crumple zone on the force exerted during a collision The student has one trolley with a spring at the front and another trolley without a spring silver foil

spring

silver foil

trolley

The student uses the arrangement in Figure 10.

trolley

silver foil

ramp

trolley

silver foil

rigid wall

too

Figure 10

000 ms

millisecond timer

After a trolley is released, it accelerates down a slope and bounces off a rigid wall

The speed of a trolley can be measured just before a collision with the wall and just after a collision with the wall.

The silver foils are connected to a millisecond timer.

The silver foils make contact with each other during the collision, so the time they are in contact can be read from the millisecond timer.

Explain how the student could investigate the effect of a crumple zone on the average force exerted during the collision.

Your explanation should include:

how to determine the force (you may wish to refer to an equation) how the effect of crumple zones may be shown in the investigation precautions that may be necessary to achieve accurate results.

(6)