Current Through Each Resistor In Series/parallel?

[powell11]

I've seen answers for either series or parallel but the circuit i'm given here has 2 resistors then another 3 which are in parallel.

20V Power supply
R1 = 12ohms
R2 = 3ohms, R3 = 10ohms, R4 = 8ohms and are all in parallel
R5 = 5ohms

I need to find the current through each resistor and its confusing me and I cant think straight, help much appreciated!

[mibn2cweus]

Find the combined (parallel) resistance of the parallel group and consider that as one virtual resistor in series with the other two in order to determine the current flowing through the circuit. Since R2,3&4 are in parallel they will all have the same voltage drop across them equal to circuit current times the combined parallel resistance and each will have a current V/Rx.

[mibn2cweus]

To check your answer add the current you calculated through each resistor in the parallel group together which when combined should equal the circuit current.

[Old_Geezer]

Yeah it is difficult to picture from the question.

The rule would be to spilt the circuit up into blocks of parallel only and serial only. Work out the effective resistance for each. Then combine blocks to work out the effective resistance over them. Eventually you will have a effective resistance for the whole load. Then divide the pd by the resistance to get the current.

Once you know that you can work out for each combined block what percentage of the current flows through it, and so on and so forth.


It may simplify as if the are parallel loads across the battery you can work each of them out individually without taking the rest of the circuit into consideration.