DiagramModerate2 marks
An electric bulb of resistance 500 Ω, draws a current of 0.4 A. Calculate the power of the bulb and the potential difference at its end.
Topic: Current, resistance and circuits
Previous-year question practice database
Answer
Exam answer
Power = 80 W; potential difference = 200 V.
Explanation
P=I²R=0.4²×500=80 W; V=IR=200 V.
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