Brainlag PlusWork done when a force moves an object, W = Fs, the joule as a newton metre, and why work against friction heats things up.
A force that moves something
When a force moves an object, energy is transferred and work is done on the object.
work done = force × distance moved along the line of action of the force
W = F s
Work in joules (J), force in N, distance in m. All three boards: recall this one.
One joule is the work done when a 1 N force moves an object 1 m, so 1 J = 1 N m.
- A 45 N push moves a trolley 20 m
- W = 45 × 20
- W = 900 J
Pushing a wall that does not move does no work on it: there is a force, but no distance moved along it.
The rest of this lesson and its 8 practice questions are in Plus.
Screen 1 of 4, free to read.
- 8 exam-style questions, marked as you go, each with a worked solution
- Anything you get wrong is saved to your flashcards