Could someone help explain something fairly basic to me (1 Viewer)

[UStoleMyBike]

https://www.youtube.com/watch?v=6TYQTrf3-n4

In this video, it shows the trolleys with the crumple zones rolling down a slope to show that with a crumple zone, there is less force being transmitted to the trolley on impact. How can you show this in terms of the numbers? What formulas would you use to calculate the force being transmitted to the trolley? I thought just the usual f=ma, but you couldn't do that just for the average force because its the force at the point of impact that counts. Would you then measure the deceleration from the period of impact?

Thanks,

 

[Fizzy_Cyst]

https://www.youtube.com/watch?v=6TYQTrf3-n4

In this video, it shows the trolleys with the crumple zones rolling down a slope to show that with a crumple zone, there is less force being transmitted to the trolley on impact. How can you show this in terms of the numbers? What formulas would you use to calculate the force being transmitted to the trolley? I thought just the usual f=ma, but you couldn't do that just for the average force because its the force at the point of impact that counts. Would you then measure the deceleration from the period of impact?

Thanks,

It is still F=ma, or F=Impulse/time (which reduces to F=ma anyway), key thing is that the time taken for the object to come to rest has increased, so if a =(v-u)/t and t increases, then a decreases and consequently, F also decreases.