View Single Post
Nov28-12, 05:26 AM
Drakkith's Avatar
P: 11,884
Quote Quote by elishamei9000 View Post
really confused about how energy can be created if a magnet in a coil attracts instead of repel? please go easy on me. how can you produce energy when your magnet attracts the induced magnetic field so it increases the velocity of the magnet so how could that produce an energy out of nothing?
Energy isn't created and magnets don't attract the magnetic field.

Quote Quote by elishamei9000 View Post
so basically if there's a bicycle dynamo, the work or energy you the cyclist gave is just the same as the energy that lit up the light? so the energy won't be an issue? please tell me if im correct
Exactly. Any generator uses external energy, typically in the form of mechanical energy, that is input into it to generate the electrical energy. You expend energy to rotate the shaft, which generates electrical current in the circuit. So this is merely energy transfer. Due to inefficiencies you cannot transfer your mechanical energy into electrical energy with 100% efficiency. Some will always be lost in the form of heat and friction.