Which of the following quantities is needed to calculate the work done by a constant force?
Magnitude of force and displacement
Work done by a constant force is the product of the force and the displacement of the object in the direction of the force: \(W = F \times s\) (in general \(W = Fs\cos\theta\)).
So both the magnitude of the force and the displacement are needed; if either of them is zero, no work is done.
The distance moved alone or the force alone gives only one of the two factors, so neither is enough. The time taken does not appear in the formula for work; it is needed for calculating power, which is work done per unit time.
Hence, Magnitude of force and displacement.
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