Question

Finding Resistance and Current in a Parallel Circuit
A diagram of a closed circuit with a power source on the left labeled 6 V. There are 3 resistors in parallel, separate paths, connected to it labeled B 10 Ohms, C 20 Ohms and D 50 Ohms. The branch with the power source is labeled A. There are vectors in the clockwise direction across all three resistors and in the branch with the power source.
Perform calculations using the circuit illustrated. Round all the numerical answers to the tenths place.

The total resistance in the circuit is
Ω.

The expected current at point A is
A.

At what point in the circuit will the current be the lowest (A, B, C, or D)?

Answer 1

1) Total resistance:
1/R = 1/10 + 1/20 + 1/50 = 0.1 + 0.05 + 0.02 = 0.17
R = 1/0.17 = 5.882... → 5.9 Ω (to one decimal)

2) Current at A (total current from the 6 V source):
I_A = V / R = 6 / 5.882... = 1.02 A → 1.0 A (to one decimal)

For reference, branch currents are:
- B: I_B = 6/10 = 0.6 A
- C: I_C = 6/20 = 0.3 A
- D: I_D = 6/50 = 0.12 A → 0.1 A (to one decimal)

3) The lowest current is at point D.