1. The problem statement, all variables and given/known data A metre stick is pivoted at 50cm and is in equilibrium. There is a 2.0N upwards force at the 5.0cm mark, and a 12N downwards force at the 40cm mark. Force F acts at the 75cm mark. Find force F. Assume the upwards direction is positive. 2. Relevant equations 3. The attempt at a solution The leftmost upwards force: 2 x 0.45 = 0.9 Nm (as the force would be 45cm from the pivot) The leftmost downwards force: 12 x 0.1 = 1.2 Nm Resultant leftmost force: 0.9 - 1.2 = -0.3 Nm Force F acts 0.15 m from the pivot, therefore: F x 0.15 m = 0.3 Nm. (resultant would be positive in order to counterbalance). Rearranging for F, 0.3/0.15 = 2 N. The programme marks this as incorrect.