Page 121 - ACTIVE SCIENCE 4 TOC

Water Energy : We get electrical energy from water. Dams are built to store
water from rivers. Water is then allowed to fall with a huge force from a height on

turbines. These turbines rotate and generate electricity.

Dam Hydroelectric energy

Earth : The energy we get from hot springs emerging

from the earth is called geothermal energy.

Renewable Sources Of Energy

Some energy sources that are not depleted by use
are called renewable energy. Sun, wind and water
are examples of renewable energy sources.

Non-renewable Sources Of Energy

This kind of energy cannot be renewed easily and will get exhausted one day due
to repeated use. Coal, petrol, wood, are examples of such energy sources.

Let’s Recapitulate

State whether the following statements are true or false.
1. Dams are built to store water to generate electricity. ______

2. Sun, wind and water are examples of solar energy. ______

3. The uwindmill is a device used to generate geothermal energy. ______
4. Energy can be converted from one form to another. ______

LET’S
REVISE Let’s Pronounce Together

pulley geothermal
• Force means pull or push.
gravitational muscular
• When we throw something upwards, it always falls
back to the earth. wedge renewable

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