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G5B05
How many watts are consumed when a current of 7.0 milliamperes flows through a 1,250-ohm resistance?
Pick an answer to check it.
Answer: A. Approximately 61 milliwatts
Use P = I^2 x R. P = 0.007 A x 0.007 A x 1,250 ohms = 0.000049 x 1,250 = 0.061 W, about 61 milliwatts.
Tip: Current and resistance known: P = I squared x R.