Paper 3C: Further Mechanics 1 June 2025, Question 5 13 marks
Three small balls, A, B and C, have masses 2m, 3m and 4m respectively.
The balls are initially at rest in a straight line on a smooth horizontal surface, with B between A and C, as shown in Figure 2.
Ball A is projected towards B with speed 5u and A and B collide directly. Immediately after the collision, the speed of B is 3 u
The balls are modelled as uniform spheres with equal radii.
Find, in terms of u, the speed of A immediately after the collision with B.
Reveal mark scheme
Find the coefficient of restitution between A and B.
Reveal mark scheme
After the collision between A and B, ball C is projected towards B with speed u Balls B and C collide directly. The coefficient of restitution between B and C is f
Given that there is a second direct collision between A and B
find the complete range of possible values of f
Reveal mark scheme