What is the potential difference across the source?
60 V
220 V
440 V
120 V
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Answer:
120 v
Explanation:
The two resistors have an equivalent of 20 * 30 /(20+30) = 12 ohms
10 amps of current in the circuit
v = ir
= 10 * 12 = 120 volts
Here is another way:
The two resistors are in prallel so the voltae across both is the same
use the one on the right v = ir = 4 x 30 = 120 v