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G5B03
How many watts of electrical power are consumed if 400 VDC is supplied to an 800-ohm load?
Pick an answer to check it.
Answer: B. 200 watts
Use P = E^2 / R. P = 400 V x 400 V / 800 ohms = 160,000 / 800 = 200 W.
Tip: Voltage and resistance known: P = E squared / R.