What is energy?
Energy is the ability to do work or cause change. Work is when force causes an object to move. Most of our energy comes from the Sun. The Sun heats Earth. The Sun's light energy makes plants grow.
We use many other forms of energy too. Sound energy comes from a CD player. Chemical energy runs a car's engine. Electrical energy runs many things in this kitchen.
Stored energy is potential energy. It can change into another kind of energy to do work or cause a change.
Fuel, such as natural gas, has potential energy. Long ago, plants made food using energy from the Sun. The plants died and turned into fossils that are used as fuel. When we burn this fuel, we free potential energy. Work is possible.
When you use batteries, you release potential energy. The stored energy in food, fuels, and batteries is chemical energy.
Vocabulary:
ability : có khả năng
force : lực lượng
chemical : hóa chất
engine : động cơ
stored : cất giữ
potential : tiềm năng
fossils : hóa thạch
fuel : nhiên liệu
possible : khả thi
batteries : pin
release : phóng thích
21/8/2021
Levic
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