a hair curling iron uses 13 watts of power. how long must it operate to do 1,040 joules of work?
Knowing the solution to the 4-watt night light, you ought to be able to do this one on your own. But 5 points is 5 points, so here we go: 1 watt = 1 joule/second . (1,040 joule) / (13 joule/second) = (1,040 / 13) (second) = 80 seconds .
Power of Watt = Energy in Joules / Time period in seconds 13 watts = 1040 joules / time in seconds time in seconds = 1040 joules / 13 watts time in seconds = 80 seconds It must operate for 80 seconds to do 1,040 joules of work.