Part A:(adsbygoogle = window.adsbygoogle || []).push({});

For what ratio of R1 and R2 would power dissipated by the resistor of resistance R2 be the same for circuit A and circuit B?

current for R2 of circuit A is (2EMF)/(2R1+R2)

current for R2 of circuit B is (EMF)/[(R1^2/2R1) + R2)

Part B:

Under which of the following conditions would power dissipated by the resistance in circuit A be bigger than that of circuit B? Choose the most restrictive answer.

R2<R1

R2>R1

R2<2R1

R2<.5R1

Equations used:

P = IV = I^2 x R = V^2 /R

Attempt:

I understand since R and P is same for both i only have to make the 2 currents equal.

(2EMF)/(2R1+R2) = (EMF)/[(R1^2/2R1) + R2)

I haven't taken physics or math class in 2 years so I'm kinda unsure on how to continue.

Since EMF is constant can I just remove it?

For part B just by plugging in numbers R2>R1 works but im not certain

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# Homework Help: Power Dissipated for 2 different circuits

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