NATURAL SCIENCE {term 3}

Energy

Energy ability of a system to do work

Renewable energy

Energy from sources that cannot be used up or exhausted and can be replenished

Examples of renewable energy sources

• Hydropower

• Solar power

• Wind power

• Wave power

• Biofuel

Nonrenewable energy

Energy from sources that will be used app eventually and cannot be replenished

Examples of nonrenewable energy sources

• Coal

• Oil

• Gas

• Uranium

Advantages and disadvantages of using non-renewable energy sources

Advantages. Disadvantages. Sells fuel anywhere. Pollutes environment

Makes lots of power. Finite resource

Can be stored Health risks

Fossil fuels

Fuels that were made from living matter a very long time ago

Why we need to use more renewable energy sources

we need to use more renewable energy sources in South Africa because it is better for the environment and less expensive

• Potential energy

Elastic potential energy

Gravitational potential energy

Chemical potential energy

Elastic potential energy

energy stored in a stretched or compressed object

gravitational potential energy

Potential energy that is stored in an object because of its position above Earth

Chemical potential energy

Energy stored in the particles of substances

The law of conservation of energy

The law of conservation of energy states that cannot be created or destroyed but can be transferred to transformed

Independent variable

Is something you add or remove to test something

Dependent variable

It is the thing you test and is the effect because of certain factors or conditions

Energy system

Different parts that work together to store , use or give out energy so that the specific task can be done

Energy transfer

movement of energy from one object to another or the change of energy from one to another

thermal energy

Energy produced by heat

Temperature

How hot or cold and object is

Difference between potential energy and kinetic energy

Kinetic energy is the energy an object has because it is moving. Potential energy is stored energy

Heat

energy transferred from a place or an object with higher temperature to a place or an object with a lower temperature

How does heat energy move

Heat energy will always move from the warmer object to the colder object