UNIT 6. ENERGY 1.- What are you going to study 2.-Find the words. You can use your dictionary or a computer. MAIN LANGUAGE Source
Pollute
Damage
Run out
Waste
Recycle
Ruin
Wind
Burn
Blow down
Torch
renewable
Reduce
Reuse
Recycle
Light bulb
Turn on
Turn off
Coal
Natural gas
Fuel
6.1 ENERGY. 6.2 FORMS OF ENERGY. 6.3 WHERE DO WE GET ENERGY? 6.4 USING ENERGY EFFICIENTLY. 6.5 WHAT IS A MACHINE?
UNIT 6 ENERGY 6.1– ENERGY 1. - ENERGY
Energy is the ability to do a work and the ability of matter to produce changes. All living things and machines need energy in order to work and move.
The wind has got energy. It has got the ability to move a boat or blow down a tree.
A fuel like petrol has got energy. When petrol burns, it moves the parts of an engine.
Foods have got energy. The food that we eat allows us to move, write, think and react. To carry out the three vital functions.
The Sun produces a lot of energy. The Sun can burn our skin, make plants grow and warm the Earth´s surface.
6.2 FORMS OF ENERGY There are many different forms of energy.
Light energy comes from sources of light such as candles, the Sun or a torch.
Electrical energy comes from batteries, generators and power stations. Lightning is electrical energy.
Thermal energy is the energy matter has got depending on its temperature. Fires, stoves and radiators give out heat because their temperature is higher than their environment.
Mechanical energy is produced by movement. For example, the energy of water flowing in rivers.
Energy from fuel comes from burning coal, oil and natural gas.
Chemical Energy , is the energy we get from the food we eat
Kinetic Energy is the energy of matter in movement. For example when you ride a bike you use kinetic energy
ELECTRICAL ENERGY
FORMS OF ENERGY
LIGHT ENERGY
KINETIC ENERGY THERMAL ENERGY
MECHANICAL ENERGY
CHEMICAL ENERGY
ENERGY FROM FUEL
6.3 WHERE D0 WE GET ENERGY. We use energy for many things in our daily lives. We use it to keep warm, for light, to work machines and to move objects. We get the energy we use from different sources. Energy sources are resources from which we obtain energy. There are renewable and nonrenewable energy sources. RENEWABLE ENERGY SOURCES Renewable energy sources regenerate continually in a natural way. They can never run out. The Sun, the wind and moving water such as rivers, waves and tides are sources of renewable energy.
NON- RENEWABLE ENERGY Non- renewable energy sources are produced slowly. They can run out because we use them quickly and don´t let them regenerate. Nature takes millions of years to make these energy sources.
Coal is used as fuel in industry and for heating our homes.
Oil is processed in oil refineries to produce fuels such as diesel, gas, butane and petrol.
Natural gas is a fuel that has many uses. We use it in boilers to heat our homes and for cooking with our ovens.
6.4 USING ENERGY EFFICIENTLY
Our modern world uses a lot of energy. The energy we use comes mostly from nonrenewable sources. These energy sources have allowed us to improve our quality of life. However, some of them create problems.
Petrol, diesel and coal produce gases that pollute the atmosphere and damage people´s health.
We are consuming these energy sources very quickly. Some of them are starting to run out.
Large facilities for producing energy can be ugly. They ruin the natural landscape.
Some forms of energy create dangerous waste products. Batteries, for example, have to be disposed of safely.
REDUCE, REUSE AND RECYCLE
REUSE: To use something again. REDUCE: To cut down the amount of waste you make. RECYCLE: To make new products from materials you don not use again.
6.5 WHAT IS A MACHINE? A machine is any object that we use to perform a task with less effort or more speed. They help us to save time and energy.
SIMPLE MACHINES Simple machines consist of just one piece or very few pieces. They work with one movement. Examples: An inclined plane, a lever, a wheel, a pulley ...
COMPOUND MACHINES Compound machines are made from many parts. Many of these parts are simple machines. Compound machines are very efficient because they use less energy to greater effect. Examples: A motor, electrical appliance ...
QUESTIONS 1. - Choose the correct definition of energy: a) Something that can explode. b) The ability of an object to move. c) The ability of matter to produce changes. 2. - Complete the descriptions of different forms of energy with the words in the box. Electrical
fuels
light
mechanical
thermal
a) …………………energy comes from sources of light such as the Sun. b) …………………….power comes from batteries and power stations. It is transported by electrical pylons and power lines. c) ……………………energy is the amount of energy matter has got depending on its temperature. d) We got energy from burning………………….like coal and oil. e) ………………….energy is produced by movement, such as the water in rivers. 3. - Match the sentences halves about energy: a) The wind………….
a) ……give us energy to move and think.
b) Fuel…….
b)…….gives us heat and light.
c) Foods…….
c) ……moves sailing boats.
d) The Sun……
d) ……powers machines like cars.
4. - Copy and complete the table with the words in the box Battery Light bulb Electrical energy
candle coal electricity pylon moving water Light energy
natural gas Energy from fuel
fire
generator
power line Mechanical energy
oil radiator
Thermal energy
5. - Are these sentences True or False? Correct the false ones. a) There are very few forms of energy. b) The amount of thermal energy something contains depends on its temperature. C) Mechanical energy is produced by light.
6. - Match the vocabulary to the definitions. a) Energy sources
a) to have nothing left of something.
b) Regenerate
b) resources that give us energy.
c) Run out
c) to produce more of something.
7. - Choose the correct answers: a) We use energy for few/ many things in our daily lives. b) Renewable energy sources regenerate continually/ occasionally. c) These energy sources can never run away/run out. d) Wind turbines convert the mechanical/ thermal energy of the wind into electricity. 8. - Name four things we use energy for.
9. - Name sources of renewable energy and sources and sources of non-renewable energy.
10. - Are these sentences True or False? Correct the false ones. a) Our modern world doesn´t use much energy. b) The population of the world is growing. c) The energy we use comes mostly from renewable sources. d) Coal is used in car engines. 11.- What is a machine? 12. - Choose the correct answers: a) Simple machines have many pieces/few pieces. b) Ramps reduce/ increase the force necessary to raise something from one level to another. c) The force exerted at one end of a lever is transmitted to the other end with more/ less power. 13. - Can you think of any machines we have to help us do the housework? 14. - What is a compound machine? 15. - Classify these objects into those that have got and have not got a motor. Bicycle bus helicopter roller skates Sailboat skateboard speedboat surfboard Have motor: Do not have motor: