Ohm's Law, Joule's Law, a Picture & a Video

[matte]

Sorry if this has been posted before.

First, via the venerable jennypdx [http://arendurance.wordpress.com/], a video - http://www.youtube.com/watch?v=0W83SOfSJoQ . Is a good intro to electrical things, including Ohm's law.

The guy presenting the video has a nice trick, which actually seems like it will be a huge help to me during the exam: Draw the two equations in triangles.

unnamed.jpg

By covering the variable you are trying to solve for, you see the equation to use. Example - solving for Resistance in Ohm's law gives me V/I [Voltage / Current {Amps}]; similarly, solving for current with Joule's gives me P/V [Watts / Volts].

Seems silly, but visual representations like this help me remember. Also, apologies for the terrible handwriting [especially the Greek].

[archatl]

Triangle/ thumb trick is very good. THX

[kyeric]

Very handy and a good link. Thanks for sharing!