# Worksheet: Units of Energy

In this worksheet, we will practice converting between the S.I. unit of energy, joules, and the units of energy more commonly used to describe energy production, such as the kilowatt-hour.

Q1:

What is J in kilowatt-hours?

Q2:

What is 7.8 kWh in joules?

Q3:

What is J in gigawatt-hours?

• A 1,500 GWh
• B 9,800 GWh
• C 6,300 GWh
• D 4,500 GWh
• E 3,600 GWh

Q4:

How many joules are there in 230 GWh?

• A
• B
• C
• D
• E

Q5:

How many joules are there in 1 kilowatt-hour?

Q6:

How many joules are there in 1 watt-hour?

Q7:

Which of the following is the correct definition of a watt-hour?

• AA watt-hour is the amount of energy transferred by a process that has a power of 1 watt and acts for 1 hour.
• BA watt-hour is the amount of time it takes for a 1-watt device to transfer 1 joule of energy.
• CA watt-hour is the amount of time it takes for a process to increase in power from 0 watts to 1 watt.
• DA watt-hour is a measure of the power of a process that is equivalent to the transfer of 1 joule of energy in 1 hour.
• EA watt-hour is the amount of energy that an electrical device transfers in 1 hour.

Q8:

What is 33,840 kJ in kilowatt-hours?

Q9:

What is 4.50 kWh in kilojoules?