# Homework Help: Graph of Power Generator

1. Nov 14, 2009

### joeykeys

1. The problem statement, all variables and given/known data
A generator is made from a 100 turn coil, 5.0 cm by 4.0 cm, placed in a magnetic field of strength 0.20 T. The coil rotates at 50 revolutions per second.

http://two.xthost.info/joeykeys/Picture%205.png

Sketch a graph of the output voltage of the coil for one cycle if timing begins at the position where the coil is perpendicular to the magnetic field. Indicate the appropriate values on the voltage and time scale. (3 marks)

http://two.xthost.info/joeykeys/Picture%206.png

2. Relevant equations

E = NBAw = 100 (0.2) (0.05*0.04) (100*3.14) = 13 V

How could the graph look like?...
Thanks ^^*

2. Nov 14, 2009

### Delphi51

An alternative formula for the potential generated is
V = L*v*B
where v is the component of the velocity vector on the wire going into the page that is perpendicular to the magnetic field. If you picture the v vector going around with the rotor, you'll see at what angle you get the maximum and minimum potentials.
There is an animation here:
http://www.generatorguide.net/howgeneratorworks.html