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Graph of power against number of resistors in parallel

Need help with a question! You are given a graph of power against n ,number resistors in parallel, and the graph is a curve. The question asks you to predict the internal resistance.

Reply 1

lerjj

I think: no resistors

\rightarrow

only resistance caused by internal resistance.

Oh, and

r=\dfrac{v^2}{P}

(edited 9 years ago)

Reply 2

That_average_guy

Yeah y intercept would give the power when there's only the internal resistor but I don't know where to go from there to actually get the internal resistance

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Reply 3

Stonebridge

Maximum power transfer theorem!

Reply 4

That_average_guy

What's the maximum power transfer theorem?

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Reply 5

Stonebridge

Original post by That_average_guy

What's the maximum power transfer theorem?

Posted from TSR Mobile

Look it up on Google!
Look for relationship between internal resistance and external resistance at maximum power.

Reply 6

That_average_guy

Ok will do, thank you!

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Reply 7

That_average_guy

Original post by Stonebridge

Look it up on Google!
Look for relationship between internal resistance and external resistance at maximum power.

I've had a look at the theorem and I'm pretty sure I now understand. Would I be right in saying that in order to find the internal resistance I would have to look at the resistance when the power is at a maximum?