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#4) A railway car with mass m1= 1000kg is rolling along at v1 =2 m/s. It rolls into bigger car at rest. The bigger car has mass m2 = 3000kg.
a. What is the initial momentum of car 1?
b.What is the initial momentum of the system?
The cars collide. Suppose car 1 is sent rolling backward at 0.1 m/s (that is, v1 = -0.1 m/s.)
c. What is the new momentum of car 1?
d. What is the new momentum of car 2?
e.What is the velocity of car 2?
Conservation of momentum: momentumSYSTEM1 = momentumSYSTEM2
momentumSYSTEM1=momentumCAR1i+momentumCAR2i
momentumSYSTEM2=momentumCAR1F+momentumCAR2F
momentumSYSTEM1 = m1iV1i+m2iV2i
momentumSYSTEM2= m1fV1f+m2fV2f
Initial momentum of car1 = m1V1i = 1000*2 =2000 kgm/s
Initial momentum of car2 = m2V1i = 3000*0 = 0 kgm/s
Initial momentum of system = initial momentum of car1 + initial momentum of car2 = 2000 kgm/s
Final momentum of car1 = 1000* (-0.1) = -1000 kgm/s
Final momentum of car 2 = (2000 = -100 + finalmomentumCAR2). FInalmomentumCAR2 = 2100 kgm/s
FinalmomentumCAR2=m2fV2f = 2100 = mv. 2100= 3000(v).
FinalvelocityCAR2= v= 2100/3000 = 0.7 m/s