Please answer the following question: A railroad handcar is moving along straigh
ID: 1429188 • Letter: P
Question
Please answer the following question:
A railroad handcar is moving along straight, frictionless tracks with negligible air resistance. In the following cases, the car initially has a total mass (car and contents) of 200 kg and is traveling east with a velocity of magnitude 5.50 m/s. Find the final velocity of the car in each case, assuming that the handcar does not leave the tracks. An object with a mass of 24.0 kg is thrown sideways out of the car with a speed of 2.50 m/s relative to the car's initial velocity. An object with a mass of 24.0 kg is thrown backward out of the car with a velocity of 5.50 m/s relative to the initial motion of the car. An object with a mass of 24.0 kg is thrown into the car with a velocity of 5.80 m/s relative to the ground and opposite in direction to the initial velocity of the car.Explanation / Answer
B)
initial momentum = 200*5.5 = 1100 Kgm/s
with respect to ground, 24 Kg mass will move with velocity (5.5-5.5) = 0 m/s
remaining mass = (200-24)Kg
final momentum = 24*(0) + (200-24)*v = 176*v
use conservation of momentum:
176*v = 1100 Kgm/s
v = 6.25 m/s
Answer: 6.25 m/s
C)
with respect to ground, 24 Kg mass will move with velocity 5.8 m/s
initial momentum = 200*5.5 + 24*5.8= 1239.2 Kgm/s
final mass = (200+24)Kg
final momentum = (200+ 24)*v = 224*v
use conservation of momentum:
224*v = 1239.2 Kgm/s
v = 5.53 m/s
Answer: 5.53 m/s