Mechanics · Work, energy & power
Chapter 1 · 3
The idea
Work done by a force
The work done by a constant force, W = Fd when the force is along the motion and W = Fd cosθ when it acts at an angle, together with work done against gravity and against resistance — and the sign convention that makes a force opposing the motion do negative work.
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Mechanics · Work, energy & power
Work done by a force
The work done by a constant force, W = Fd when the force is along the motion and W = Fd cosθ when it acts at an angle, together with work done against gravity and against resistance — and the sign convention that makes a force opposing the motion do negative work.
Why it works
Force times distance
Work is the currency of mechanics — every energy theorem in this strand trades in it. When a constant force moves its point of application through a displacement, it does work. If the force acts along the direction of motion and the object moves a distance , the work done is measured in joules () — one joule for every newton pushed through every metre. Work is a scalar — it has no direction — but it does carry a sign.Keep reading — free
The rest of the explanation, plus 3 worked examples you step through move by move.
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