Voltage drop across a resistor in a circuit

AI Thread Summary
To find the voltage drop across the top left resistor in the circuit, Ohm's Law (V = IR) is applied, where I is the current through the loop and R is the resistance of that specific resistor. The current has already been calculated in previous parts of the problem. The voltage drop can be directly determined by multiplying the current by the resistor's value. There is no need to subtract from the total voltage of the circuit; the calculation is straightforward. This method effectively provides the correct voltage drop across the resistor.
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Homework Statement



Three batteries and four resistors are connected in a loop as shown (see attachment).

What is the voltage drop across the top left resistor?

Homework Equations



V = IR

The Attempt at a Solution



This is part 3 of the 3 questions for this problem. On the other two I found the current of the loop and the voltage across points a and b.

I think that all I need to do here is multiply IR (R being the value of that resistor) but that just seems too easy. Do I have to subtract it from the total voltage for the circuit or something?
 

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  • circuit.jpg
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All you need to do is use loop laws to find the current, and then you can find the voltage drop over the resistor using Ohm's law.
 
Ok. I already found the current in the circuit and I assumed that I needed to use Ohm's Law to find the voltage drop, but my question is whether I just multiply the current in the loop by the value for the specific resistor and that's it, or if I have to do something after that step?
 
That's it.
 
Awesome. Just seemed too easy so I thought maybe something else was going on. Thank you
 
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