Which is the value of 1 kWh of energy converted into joules

Which one of the following is the value of 1 kWh of energy converted into joules?

  1. 1.8 × 106 J
  2. 3.6 × 106 J
  3. 6.0 × 106 J
  4. 7.2 × 106 J

Answer

1 W = 1 J/s

Since there are 60 seconds in a minute and 60 minutes in a hour,

1 h = 60 × 60 s = 3600 s

1 kWh = 103 J/s × 3.6 × 103 s

1 kWh = 3.6 × 106 J

The correct option is B.