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## Main Question or Discussion Point

1. a small car and a big truck collided. as newton's 3rd law states, they should apply the same amount of force with each other. so if the big truck has a mass of (just to make it simple) 5kg and acc of 2m/s to the right and the small car has a mass of 2kg and acc of 3m/s to the left. (Ftruck=+10N, Fcar=-6N) of course the car has a smaller force, but as stated above, upon collision, they should have the same force? how do i determine that force given their initial[?] forces. please clarify me on this. a follow up question would be that if given the initial forces acting on two known masses, how can i determine the force upon their impact?

2. i've read in a magazine that when 2 motorbikes collide, they'll produce roughly 124K N of energy. Given that their initial velocity is the same at 50mph (22.2m/s, one positive and one negative of course since this is just one dimensional collision) and their masses are 80 and 90kg with a collision time of 0.015s, i was wondrin with how they derived this 124K N of force. I can't use conservation of momentum (and F=m[tex]\Delta[/tex]v/[tex]\Delta[/tex]t also) since i can't assume that they have zero final velocity as that would mean that they have the same mass. how should i use the given variables?

please enlighten me guys. ^^

2. i've read in a magazine that when 2 motorbikes collide, they'll produce roughly 124K N of energy. Given that their initial velocity is the same at 50mph (22.2m/s, one positive and one negative of course since this is just one dimensional collision) and their masses are 80 and 90kg with a collision time of 0.015s, i was wondrin with how they derived this 124K N of force. I can't use conservation of momentum (and F=m[tex]\Delta[/tex]v/[tex]\Delta[/tex]t also) since i can't assume that they have zero final velocity as that would mean that they have the same mass. how should i use the given variables?

please enlighten me guys. ^^

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