Parallel circuit with internal resistance

dbag123

Homework Statement
Calculate current through the source
Homework Equations
P=UI, U=RI
4 resistors R1= 10 Ohm R2= 7 Ohm R3= 6 Ohm R4 = 18 Ohm, internal resistance of source is 0,5 Ohm and supply voltage is 27V

Total resistance in parallel resistors 1/R = 0.465 taking the inverse of that i get 2,15 Ohm. Add to that the internal 0,5 and the total comes out to 2,65 Ohm.

Total current would then be U/R --> 10,2A rounded up. If it is true that in a parallel circuit the voltage stays the same, than it stands to reason that the sum of the currents should add up to 10,2 but they dont. i get a total current of 12,577 just for the 4 resistors. What is happening here?

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dbag123 mjc123

If the supply voltage is 27V, the internal resistance is 0.5Ω and the resistance of the parallel set is 2.15Ω, what is the voltage drop across the parallel resistors? (hint: it is not 27V)

• Delta2

21,93V

Last edited:

mjc123

And if you have a voltage drop of 21.93V across the 4 parallel resistors, what is the total current through them?

dbag123

10,2A

"Parallel circuit with internal resistance"

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