A horizontal arm in a workshop lifting mechanism is pivoted at its centre. The arm's weight is negligible. A downward force of 240 N acts 0.75 m to the left of the pivot, and a downward force of 120 N acts 1.5 m to the right. The arm is initially balanced and horizontal. The 240 N force is moved to a point 0.50 m to the left of the pivot. The other force stays in place.
Explain the direction in which the arm begins to turn after the force is moved.
102 exam-style questions on Edexcel GCSE Physics 9.2 Moments, covering 9.2.1 Rotational effects of forces and moments, 9.2.2 The principle of moments, and 9.2.3 Levers and gears. Each one has a worked solution and a mark scheme showing where the marks go.