Self working Light Bulb

This idea did somehow strike to me a few days ago. In my house we often used to charge the emergency light. I have been studying about Electricity and Magnetism chapter.

         

          I thought for a while to get a good way to solve this problem of charging. I don’t want to spend my money on this small light. I thought for a good physics way to get light with the lowest cost. But I finally found a light not only with lowest cost but also can give light for a long time.

         

The idea is very simple. It just deals with the faraday’s law of inductive effect that is changing magnetic field produces Electromotive force in a closed loop. But all we need is a strong magnet and a coil of many closed loop wires and a stand.

         

          It is just like a simple pendulum that is oscillating inside a closed loop. The model will be similar to the below diagram,

         

          The continuously changing magnetic field due to the magnet induces current in the closed loop. To get a maximum current, the magnet should have maximum strength and the coil should have maximum closed loops.

          To get rid of the resistance effect from the environment, the whole setup can be brought into a box of vacuum inside. So the external effects can be neglected. But this will not behave as a 100% efficient light source since there are resistive effects inside the closed loop itself. And there is resistance present in it and continuous current will heat up the coil and the resistance itself will increase with respect to temperature.

         

         The current is Alternating Current by means of the direction change in each period of the oscillation. But it will serve as a good light source.