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In this problem, we have two resistors, r1, which is equal to r, and r2, which is equal to 2 times r.
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And they're connected to a battery.
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And we want to figure out which one dissipates more power depending on how they're connected to the battery.
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The first, in part a, would be when they are in series, and in part b, when they are in parallel.
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So there's a few key things we need to know.
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So when the resistors are connected in series, that means they have the same current flowing through them.
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So the current will be the same in the first resistor and in the second resistor.
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For part b, when they're in parallel, that means each resistor has the same voltage across it.
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So the voltage will be the same for resistors 1 and resistors 2.
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And part a, when they are in series, since we're looking at current, then the equation we can use in series will be power is equal to current square times the resistance.
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And for parallel, since we're looking at voltage, the voltage being the key thing, then the equation here for power will be power is equal to the voltage squared divided by the resistance.
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So in part a, again here the resistors are connected in series, so they have the same current.
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So if you look at the equation for power for the first one, power will be 1 will equal current squared times r1.
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And again, they have the same currents here when they're in series.
02:02
And then the second register, p2, we have i squared times r2...