Question

Ten identical electric bulbs , each rated 220 v , 50 w are used in parallel on 220 v line for 10 hours per day in a month of 30 days . Then the electrical energy consumed in kilowatt hour is

• A. 15
• B. 150
• C. 1500
• D. 15000

Answer 1

Answer: (B)

150

Power consumed by each bulb $=50$ watt

Power consumed by $10$ bulbs $=50\times 10=500$ watt

Energy consumed by $10$ bulbs $=P\times t$

$=500\times t$

$=500\times 10\times 30$ watt hour

$=150000$ watt hour $=150$ kilowatt hour