(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

1) Where I(t) = Iocoswt, and V' is the voltage across an inductance V' = L dI/dt, Im asked to work out the time average of <I V' >..

when i work it out, the answer comes to zero...any ideas why?

2)I'm asked to sketch I(t) = Acos(w1 t)cos(w2 t) where w2 << w1...

is this just fast oscillations of speed (w2) within a boundary that is itself oscillating (more slowly..) ? so a cos graph within a cos graph with bigger period?

3) Find the bandwith of the signal I(t) = A cos^2 (wt) cos(10wt)..

I know bandwith is the randge of angular frequencies present in I, but here its not just 10wt-wt is it? How do I work it out?

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Some Electricity Questions!

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