Mathematics 9709 · AS & A Level · Newton's laws of motion
Newton's laws of motion — practice question
Two particles with masses $1.3\,\text{kg}$ and $0.7\,\text{kg}$ are joined by a light inextensible string passing over a fixed smooth pulley. The particles are initially at the same vertical level, with the string taut. Each particle is $2\,\text{m}$ above a horizontal plane, and each is $4\,\text{m}$ beneath the pulley. The particles are then released from rest.
(i(a))
Determine the tension in the string before the $1.3\,\text{kg}$ particle reaches the plane.
(i(b))
Determine the time taken for the $1.3\,\text{kg}$ particle to arrive at the plane.
(ii)[4]
Determine the greatest height reached by the $0.7\,\text{kg}$ particle above the plane.
Worked solution & mark scheme
This 4-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Newton’s Second Law for the particles gives: $1.3g - T = 1.3a$ and $T - 0.7g = 0.7a$” …