AC generator vs DC motor

[Crash867]

Hi

I've recently got an assignment to help us understand electricity and how current flows. The one question asks me to explain the basic principles on which a DC motor and AC generator work using a graph! Any ideas what they mean? Its worth 8 marks and I have no idea what it means.

Any ideas?

 

[DA-LION-619]

Try Wikipedia for your school work

 

[AndyC]

DC = Direct Current. DC motor works with a DC voltage constantly driving altternate armature coils.

AC = Alternating Current. AC motors.... don't get me started...

 

[Crash867]

I understand that but how on Earth do I represent that on a graph? I can explain it pretty easily and I understand how they work, it's the graph part that gets me

 

[Lycanthrope]

I understand that but how on Earth do I represent that on a graph? I can explain it pretty easily and I understand how they work, it's the graph part that gets me

The signals, perhaps?

 

[Johnatan56]

Graph wise DC is a straight line, while AC would be e.g. 0.2 sec above graph then the same below the x axis. AC section be sure not to join them!

 

[plod]

Must mean the current flow or vlotage?

It is the only thing I would think you can draw in a graph from. The AC looks like a sine wave and DC a flat line