Question

express 5 kwh in joules ​

Answer 1

18000000 joules

One kilowatt-hour is equivalent to the energy of 1,000 joules used for 3,600 seconds or 3.6 million Joules. In equation form: 1 kWh = 3.6 million J.

A 100 watt light bulb uses 100 watts of power. To convert the power in watts to kilowatt-hours, multiply 100 watts by 1 hour, then divide by 1,000 to find the energy usage in kWh. If electricity costs $0.12 per kWh, then a 100 watt light bulb will cost 1.2 cents per hour that it's on.