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Momentum & its conservation. Car truck collision. F c. F t. F t = m t. change in v t time. F c = m c. change in v c time. F c time = m c change in v c. F t time = m t change in v t. F c time + F t time = m c change in v c + m t change in v t.
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Car truck collision Fc Ft Ft = mt change in vt time Fc = mc change in vc time Fc time = mc change in vc Ft time = mt change in vt Fc time +Ft time= mc change in vc+mt change in vt (Fc+Ft)time=change in mcvc+change inmtvt (Fc+Ft)time=change in(mcvc+mtvt)
Car truck collision Fc Ft (Fc+Ft)time=change in(mcvc+mtvt) Newton’s 3rd law: Fc= -Ft (Fc+Ft)time= 0 0 = change in(mcvc+mtvt) mcvc+mtvt stays constant!
Momentum = mv mcvc = momentum of car this changes this changes Mtvt= momentum of thruck mcvc+mtvt = total momentum this stays constant Before = -40 After = -40 Momentum is conserved!
True for all collisions before =+20 after =+20 visit www.physicsclassroom.com/mmedia/index.html
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