Physics 9702 · AS & A Level · Equilibrium of forces
Equilibrium of forces — practice question
A climber is held against a vertical wall by a rope, as illustrated in Fig. 2.1. The climber’s weight $W$ is $520\,\text{N}$. The rope, with negligible weight, is fastened to the climber and to a fixed point $P$, where it is inclined at an angle of $18^\circ$ to the vertical. A reaction force $R$ acts at right-angles to the wall. The climber is in equilibrium.
(a)[2]
State the conditions required for the climber to be in equilibrium.
(b)[2]
Complete Fig. 2.2 by drawing a labelled vector triangle to show the forces acting on the climber.
(c(i))[2]
Use force resolution or your vector triangle to determine the tension $T$ in the rope.
(c(ii))[1]
Use force resolution or your vector triangle to determine the reaction force $R$.
(d)[1]
As the climber moves up the wall, the angle the rope makes with the vertical increases. Explain why the magnitude of the tension in the rope increases.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Resultant moment $= 0$ / total clockwise moments equal total anticlockwise moments” …