Question

A 100 W electric bulb is used for 5 hours daily and four 50 W bulbs are used for 5 hours daily. Calculate the energy consumed (in kWh) in the month of January.

• A.
  45
• B.
  50.5
• C.
  46.5
• D.
  55.5

Answer 1

The correct option is C

46.5
Energy used by 100 W bulb = P × t
= 100 × 5 = 500 Wh
Energy used by four 50 W bulbs
= 4 × 50 × 5 = 1000 Wh
Total energy per day
= 500 + 1000 = 1500 Wh
= 1.5 kWh
Number of days in January = 31 days.
Energy consumed in January = 31 × 1.5 = 46.5 kWh.