Physics (AS & A Level) · Oct / Nov 2017 · Paper 13 · Question 10

Two railway trucks of masses m and 3m move towards each other in opposite directions with speeds 2v and v respectively. These trucks collide and stick together. What is the speed of the trucks after the collision?

1. A\frac{v}{4}
2. B\frac{v}{2}
3. Cv
4. D\frac{5v}{4}

As printed in the paper