Energy used by a 1,500 W hair dryer in 10 minutes

Answer: energy = 900,000 J (in watt-hours 250 Wh, in kilowatt-hours 0.25 kWh).

What we know

  • Power: 1500 W
  • Time: 10 min = 600 s (converted to the unit the formula takes)

Step by step

Given
P = 1500 W, t = 600 s
Formula
E = P × t
Substitute
E = 1500 × 600
Result
E = 900,000 J

All results

Energy900,000 J
In watt-hours250 Wh
In kilowatt-hours0.25 kWh

Open the watts to joules calculator with these numbers → and change any of them.

The physics

A watt is one joule per second, so energy is simply power multiplied by the time it flows: E = P × t. Run a 60 W bulb for 60 seconds and it consumes 60 × 60 = 3,600 joules. The joule is the SI unit of energy; the watt is the rate at which that energy is delivered or used.