Mathematics 9709 · AS & A Level · Forces and equilibrium

Forces and equilibrium — practice question

Three coplanar forces, with magnitudes $15\,\text{N}$, $25\,\text{N}$ and $30\,\text{N}$, act at point $B$ on the line $ABC$ in the directions indicated in the diagram.
(i)[6]

Determine both the magnitude and the direction of the resultant force.

(ii)[3]

The force with magnitude $15\,\text{N}$ is now replaced by a force of magnitude $F\,\text{N}$ acting in the same direction. The new resultant force has zero component in the direction $BC$. Find the value of $F$, and also determine the magnitude and direction of the new resultant force.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: Resolve the forces horizontally or vertically

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