I just don't understand circuits... at all...

[MarkyD]

1 hour ago, Stub Mandrel said:

Start witha 1 ohm resistor with 1 volt across it, so that (I =VR) 1 amp flows. Thiscreates a power of 1 watt P=IV P= 1x1  P=I^2 x R = 1x1x1  P= V^2/R = 1x1/1 = 1

Should be I = V/R

[Scott]

yes, thats correct and thats what my equation gives you. I=E/R....2/2=1

Your equation I=VR (I=VxR) would give you 4 amps.... 2x2=4

I'm not trying to be picky but the op needs the correct equation

[Stub Mandrel]

Sorry folks, looked straight though my own error. I have corrected the post to avoid confusing the OP, rather than to hide my mistake.

[Scott]

Not a problem Neil. I really was starting to question my own memory. It seems to let me down more and more often these days

[Uranium235]

Cor blimey, that brings back a few memories of my YTS days

A nice simple project is to build a smoothing circuit and/or transformer (probably still the most efficient design man has ever made! Usually about 95-99%). Though it helps to have an oscilloscope so you can see the before and after effects of smoothing.

[Ganymede12]

I think I see my problem. The constant I was looking for is EMF, and it's the terminal P.D is what's varying? 

The question wasn't directly linked to the question in the past paper, I was just trying to get my head around how the equations worked together. 

Thanks for the help guys! I haven't been on the forums recently became of my A-levels but I'm glad to see that the community here is as kind and helpful as ever. ?