A-level Physics (Advancing Physics)/Generators/Worked Solutions

1. Draw diagrams of an alternating current, the 'direct current' produced by a DC generator, and this current once it has been smoothed with a capacitor.



2. What is the phase difference (in radians) between the voltages produced by a three-phase generator?

$$\frac{2\pi}{3}^c$$

3. According to Faraday's law, what three things will increase the amplitude of the emf created by a generator?

$$\epsilon = -\frac{dN\phi}{dt}$$

So, more coils, a stronger magnetic field or a higher frequency of rotation will increase the amplitude of the emf.

4. If an albatross touched two power cables carrying AC in phase, what would happen?

Nothing - there is no potential difference between the two cables.

5. What would happen if the two cables carried three-phase power?

Unfortunately, dead albatross - there is potential difference between the two cables.