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Sam Brown

Hi Anthony,

Actually, it doesn’t mean that the voltage going to R1 is cut in half. Nor should you think in terms of which side the voltage is coming from or going to. Let’s just break this question down into what we know about this circuit, and series circuits in general:

1. The entire circuit is supplied with 240 volts. You can tell because you have both L1 and L2. When figuring out voltage drop, you don’t have to worry about what voltage is coming from which side. All that matters is that your source voltage is 240.

2. Voltage drop in series circuits is divided up between loads proportional to their resistance. In other words, if one load has 2 times more resistance than the other, then it will drop 2 times more voltage than the other.

3. The voltage drop across all loads in a series circuit will always add up to equal the source voltage.

From here, you should just have to do some simple math to figure out the answer. R1 will drop 2 times more voltage than R2, and both of their voltage drops combined will add up to 240. Let me know if any of this still isn’t clear.