How Do You Calculate Current Through a Resistor in a Parallel Circuit?

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To calculate the current through a resistor in a parallel circuit, first determine the total resistance (Rtotal) of the parallel resistors. Use the electromotive force (e.m.f.) as the supply voltage, while accounting for the internal resistance of the battery, which acts in series. The terminal voltage can be calculated using the formula Vab = e.m.f. - Ir, where I is the total current and r is the internal resistance. Apply Ohm's Law (IR = e.m.f. - Ir) to find the current through each resistor. This approach allows for accurate calculations of current and voltage drops in the circuit.
QueenFisher
i've been given this circuit, i know the e.m.f. and internal resistance, it has 2 resistors connected in parallel so i can work out Rtotal, but i need to work out the current through one of the resistors. can anyone point me in the right direction?
thanks :biggrin:
 
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Well, once you know R you can calculate the total current. With the current, you can calculate the volt-drops certain resistances, etc. That's generally the approach to take.
 
so do i take the e.m.f. as being the supply voltage in this case? cos i can't think of any other way to find it
 
The internal resistance [of the battery] acts as if it were a resistor in series with the battery. You could find the ternimal voltage.
V_{ab} = \varepsilon - Ir

\varepsilon = Emf
r = internal resistance

USing ohms law we get.
IR = \varepsilon -Ir

Where R is the 2 resistors in parallel.

I'm sure you can take it from here.
 
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Thread 'Correct statement about size of wire to produce larger extension'

Thread 'Correct statement about size of wire to produce larger extension'

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