Q19. A 24V car battery delivers power to a circuit. The circuit has a 3A fuse. The measured resistance in the circuit is 8.2Ω. Will the fuse blow?
Use V = IR, where V is voltage in volts, R is resistance in ohms and I is current in amps.
Answer and commentary
We have V = 24 and R = 8.2. We need to know if this gives a current of more or less than 3 amps. More and the fuse will blow!
V = IR
24 = I x 8.2
24 รท 8.2 = I
I = 2.9268...
The current is just less than 3A. So, the fuse will not blow.
Answer: No - the fuse will not blow.
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