Two trains are heading in opposite directions on the same track. Train X has a mass of 16000kg and a speed of 2.8m/s. Train Y has a mass of 12000kg and a speed of 3.1m/s. At what speed do the joined trains move off together immediately after the collison?

Remembering that if the velocities are in different directions they have different signs:Total momentum before=Total momentum afterMomentum=mass x velocityTotal momentum before= (16000x2.8)+(12000x(-3.1))=7600kgm/sCombined mass =28000kgVelocity after collision =7600/28000 =0.27m/s (2dp)

CJ

Related Physics A Level answers

All answers ▸

What is gravitational potential energy? Why is it negative?


Given a graph of the displacement of a particle, how can you tell if it is in Simple Harmonic Motion?


A diver of mass 60kg stands on the end of a diving board (2m in length). Calculate the upward force exerted on the retaining spring which is 30cm from the start of the diving board.


Determine an approximate value for the acceleration of free fall using a tennis ball, metre ruler and a stopwatch.