Mathematics (AS & A Level) · May / June 2026 · Paper 43 · Question 7

3 m a P Q 2 kg 5 kg Particles P and Q have masses 2 kg and 5 kg respectively. The particles are initially held at rest 3 m apart on the same line of greatest slope of a rough plane. The plane is inclined at an angle a to the horizontal, where . sin 0 28 a = (see diagram). The coefficient of friction between P and the plane and the coefficient of friction between Q and the plane are both 0.2. Particle P is projected directly towards Q with speed ms 8 1 - . At the same instant, Q is projected directly towards P with speed ms u 1 - . The particles collide 0.25 s after they are projected.

Read automatically from the paper; the printed page above is exact.