Question

URGENT PLEASE ANSWER: It takes about four minutes to bake a potato in a 1000 W microwave oven. How much energy is used?

0.7 kWh
0.07 kWh
4 kWh
0.04 kWh

Answer 1

0.07 is the correct answer

Answer 2

Energy = (1,000 watt) · (1 kW/1,000 watt)· (4 minute) ·(1 hr/60 minute)

Energy = (1,000 · 4) / (1,000 · 60)  (watt·kW·minute·hour / watt·minute)

Energy = (4/60) (kW · hr)

Energy = 0.07 kWh (rounded)