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tiny-tim
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Apr14-12, 07:57 AM
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Quote Quote by sgstudent View Post
Oh, so the force acting on the piston is equal to the force acting on the water? Why is this so, since if I have a 10N force on the water there will be a reaction force of 10N on the piston so won't I have to apply 20N of force rather than 10N
are we talking about a particular device?

usually there's two pistons, we push one, and the other pushes a wheel etc

if we push the first piston with 10 N, the water pushes back on the first piston with 10 N

at the other end, the same water pushes on the second piston with 20 N, and the water pushes back on the second piston with 20 N

(so it's geared: we push the first piston, and the second piston moves half as far with twice the force)