Mathematics 9709 · AS & A Level · Newton's laws of motion

Newton's laws of motion — practice question

Particles $A$ and $B$ have masses $0.3\,\text{kg}$ and $0.1\,\text{kg}$ respectively. They are fixed to the two ends of a light inextensible string. The string runs over a fixed smooth pulley, and the particles hang vertically below the pulley. At the start, both particles are at a height of $x\,\text{m}$ above the horizontal ground (see diagram). The system is released from rest.
(a)[4]

Find the tension in the string and the acceleration of the particles.

(b)[3]

In the later motion, $B$ does not reach the pulley. When $A$ reaches the ground, it comes to rest. Given that the maximum height of $B$ above the ground is $1.2\,\text{m}$, find the value of $x$.

Worked solution & mark scheme

This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: Apply Newton’s second law to one of the particles.

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI