Study Guide
Day 5
Energy is the power to do work. We use energy so much in our daily lives that it
can be easy not to notice it. Have you ever thought of all the ways that you use
Name two ways that you used energy today:
Energy was used to create the worksheets that you are now reading. A computer
was used to write on the papers. A copier was used to print the worksheets.
Your classroom has lights so you can read these papers. These are just a few
examples of how energy is used.
The sun is the source of almost all energy on Earth. The sun is the direct source
of light and heat energy.
Some sources of energy are continuously made and replaced by nature. These
sources of energy are called renewable resources. One renewable resource is
sunlight. The sun is a very important resource. It gives us light energy and heat
energy. It helps plants grow and it keeps us warm. The sun’s energy is called
solar power or solar energy. It can be used to make electricity.
The wind and water are also renewable resources. The force of flowing water
and moving air (wind) can also be used to generate electricity. Windmills use the
energy from wind to produce electrical energy for businesses and communities.
Wood comes from trees. It has many important uses, including its use as a fuel.
Wood is also a renewable resource.
Study Guide
Day 5
4. Some sources of energy are called nonrenewable resources. These resources
take a very, very long time for nature to replace them. The fossil fuels (coal,
oil, and natural gas) are nonrenewable resources. Fossil fuels are formed
from decayed plants and animals buried in layers of rock. The formation of fossil
fuels takes millions of years.
Our world uses huge amounts of fossil fuels every day. We burn gas to run our
cars, burn natural gas to heat our homes, and burn coal to create electricity. Did
you know that electric power plants in the United States burn more than 750
million tons of coal each year? It is important to learn how to use less of our
fossil fuels. Why?
If we do not conserve or use our fossil fuels wisely, they will be seriously depleted
by the middle of the 21st century. Conserving these resources will make sure that
they are there for others to use.
Energy needs to be conserved or used wisely. Name three ways that you can
conserve energy: