00:02
We're given the following circuit.
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We have a 60 -bobob battery attached to two parallel systems, each with two resistors, r1 through r4.
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Their values equaling 3 oms, 6 oms, 12 oms, and 4 oms.
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We approach this circuit by simplifying it to the following.
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We must solve for the equivalent resistance.
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To solve for equivalent resistance, we use the...
01:09
Two following formulas, meaning that in the parallel systems of resistors, we'll add 1 over r plus r1 plus 1 over r2 until we've added all of them together, and then we'll take the inverse of that.
01:59
In series systems, we add them r1 plus r2 plus so on.
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So we'll first look at the two systems in parallel, r1 and r2.
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These are in parallel, so we add them as so.
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Similarly, we'll add r3 and r4 together, and we'll assign these to r5 and r6.
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So we can look at this circuit as this, and now we can add these together in series to find that the equivalent resistance is 5 oms.
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So now you might wonder why do we need to solve for the equivalent resistance? this allows us to find the current here at these two points.
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That's the current surrounding everything in the circuit.
04:24
This allows us to write oms law v equals ir, finding that the current in the circuit is 12 amps.
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Now let's return to our original circuit.
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We know that the current here is 12 volts, 12 amps, i'm sorry.
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And so we'll write r1, 2, 3, and 4 as following.
05:39
To solve for each resistor's current, the current across each resistor, first we have to solve for the current entering and exiting each system.
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And we know that series resistors hold the same current...