Engineering Board Exam Reviewer · Ohm's Law · medium

The voltage across a resistor is tripled and, at the same time, its resistance is halved. By what factor does the current change?

1. It becomes 1.5 times as large
2. It becomes 6 times as large
3. It becomes 3 times as large
4. It is unchanged

Answer

B. It becomes 6 times as large

Solution

I'=3V/R/2=6V/R=6I.

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