Mathematics 9709 · AS & A Level · Forces and equilibrium
Forces and equilibrium — practice question
A particle of weight $80\,\text{N}$ is attached at $B$ to a light string $AB$, which is fixed at $A$. At $B$, a horizontal force of magnitude $P\,\text{N}$ acts, making the string inclined at an angle $\theta^\circ$ to the vertical (see diagram).
(a)[4]
It is given that $P = 32$ and that the system is in equilibrium. Determine the tension in the string and the value of $\theta$.
(b)[4]
This time, you are told that the tension in the string is $120\,\text{N}$, while the particle at $B$ still weighs $80\,\text{N}$. Determine $P$ and $\theta$.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Form equations by resolving forces in one direction” …