Question

A yellow train of mass 100 kg is moving at 8 m/s towards an orange train of mass 200 kg traveling on the opposite direction on the same track at a speed of 1 m/s. What is the inital momentum of the yellow and orange trains combined?

Answer 1

Mass of yellow train, my = 100 kg

Initial Velocity of yellow train, = 8 m/s

mass of orange train = 200 kg

Initial Velocity of orange train = -1 m/s (since it moves opposite direction to the yellow train, we will put negative to show the opposite direction)

To calculate the initial momentum of both trains, we will use the principle of conservation of momentum which

The sum of initial momentum = the sum of final momentum


Since the question only wants the sum of initial momentum,

(100)(8) + (200)(-1) = 600 m/s