# Experiment - Generating electricity

In this experiment you will examine the way voltage is created when metal conductors are moved through or in a magnetic field and explore how the input of energy is related to the energy supplied from the generator.

 Aim To explore the energy produced by a hand held generator as the rate of rotation of the metal coils through a magnetic field is changed. Apparatus (Equipment) 1 x simple hand-operated generator with a suitable light globe. Method Treat the generator with care. Perform a test on the generator to ensure that the light globe will glow when the generator is spun. Once you are sure the generator is working properly, examine the generator to see what is happening when the generator starts to rotate very slowly. Ask your teacher to describe what is inside the generator. Being careful not to damage the generator, slowly increase the rate at which you are rotating the generator coils. Observe what happens to the light bulb as the speed of rotation changes. If you have a galvanometer with a centre ZERO, or a multimeter try attaching the generator to the meter and observe what happens when the generator is spun at different speeds. If interested, consult your teacher and ask whether you can observe the results using a Cathode Ray Oscilloscope (CRO). Record all your observations in the results section of your experimental write-up. Based on your observations, write a conclusion to the experiment.

## Questions

1. Is there evidence that higher energy input (faster turning of the generator handle) results in higher energy output from the generator?
2. What happened to the light globe as the generator was spun faster? Is this what you expected to happen and can you offer an explanation why?
3. Based on your observations, what determines the amount of power a generator produces?
4. If you could increase the strength of the magnetic field do you think you would generate more electrical energy if the generator was turned at the same rate as with a weaker magnetic field? Can you design an experiment that could gather evidence to test that?