A 1000-watt microwave oven takes 60 seconds to heat a bowl of soup. How many joules of energy does it use?

The microwave uses ##6000 J## of energy.
Where ##P## = Power ##t## = time and ##W## = work …
##P = 1000## watts
##t = 60## seconds
The formula for Power is given by:
##P = W/t##
Therefore:
1000 Watts = ##W/60##
So …
##W=1000(60) =6000 W## (or J=Joules)
From this we can say that a microwave oven of 1000 W uses 6000 J of in 1 minute (60 seconds).