Heat: the transfer of thermal energy from one substance to another. Electrons: the small particles inside an atom that have negative charge.

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1 GRADE 5 0

2 Energy: the ability to cause change OR to do work Kinetic energy: energy of motion Potential energy: energy of position (stored energy) Thermal energy: the energy that moves particles of matter Heat: the transfer of thermal energy from one substance to another Electrical energy:: a kind of energy that related to the movement of electric charges Electrical current : the flow of electrons. Electrons: the small particles inside an atom that have negative charge. Circuit: the path that is made for an electric current. Hydro-electrical energy: the electricity generated from the force of falling water. Biomass: organic matter, such as wood, that is living or was recently alive Nuclear energy: the energy released when the nuclei of atoms are split or combined. 1

3 Conduction: the direct transfer of thermal energy between objects that touch each other. Conductors: materials through which energy can move easily Convection: the transfer of thermal energy in moving liquids and gases Radiation: the transfer of thermal energy by bundles of energy that move in matter or in empty space (electromagnetic wave) Atom: the smallest building unit of matter Geothermal energy: the heat that produced from hot rocks under Earth's surface Fossil fuel: fuels made from dead plants and animals over millions of years. Charge: is a measure of the extra positive or negative particles that an object has. Energy transformation: energy change from one form to another. 2

4 Energy is the ability to cause changes in matter in many ways such as moving objects, changing the state of matter (from solid to liquid to gas and vice versa), etc. There are two basic kinds of energy, kinetic energy and potential energy. Kinetic energy Energy of motion Examples: Thermal energy, Electrical energy, Light energy and sound energy. Potential energy Energy of position or stored energy Examples: Chemical energy, nuclear energy Energy is obtained from different energy sources such as those shown in the following pictures. wind Nuclear energy biomass Fossil fuel The sun Geothermal energy Think about the kinds of energy that we can get from each resource Hydro-electric energy 3

5 Thermal energy can cause the particles of matter to move. When particles of matter gain thermal energy they start to move faster and become hotter Thermal energy can cause the state of matter to change as shown in the picture. Thermal energy is kinetic energy. We feel thermal energy as heat. Thermal energy can be transferred by three ways: conduction convection radiation Conductors are the materials that conduct heat easily, such as metals Insulators are the material that can t conduct heat easily (or poorly conduct heat) such as wood and plastic. Pans are made of metals which is conductors to conduct heat easily from the stove to food 4

6 Mittens are made from cotton which is insulator to allow us hold hot things In cold days we wear jackets because jackets are made of insulator so it keeps the heat inside our bodies and prevent heat from escape. Find out more about the transfer of thermal energy by visiting the following website: Matter is built up of basic units called atoms ( see the diagram) Electrons (has ve charge) The nucleus Electric energy is produced by the movement of electrons Particles of matter have a property called electric charge. When an object gains or loses electrons, it has an electric charge. An object that has gained electrons has a (-ve) charge An object that has lost electrons has a (+ve) charge Flow of electrons is called electric current. Electricity can be produced by several ways such as rotating coil between a magnet poles ( see the figure) Scientist used that phenomenon to make generators 5

7 which is used to produce electricity. Electricity can be made from many sources such as fossil fuel, biomass, 6+geothermal, wind, the sun and nuclear energy. To draw a circuit diagram, we use certain symbols such as those shown in the following frame motor switch bulb Battery (electric cell) buzzer Can be represented by This circuit This diagram to know more about circuits, visit the following sites s/flash/concepts/buildingcircuits.htm s/flash/concepts/simplecircuits.htm s/flash/concepts/experimenting.htm 6

8 Circuits can be connected in two ways Series connection Only one path for the electrons If one part is broken up, the circuit will broken and the current will stop flow Parallel connection There are more than one path for the electrons If one part is broken up, the others will keep working because the electric current will continue to flow Law of conservation of energy: energy can't be created or destroyed. N.B the previous law is correct just with respect to our life That's because energy can be created by Allah and also can be destroyed by Him Energy can change forms several times during one activity. 7

9 In the following figure, you can see an example of energy transformation Light energy from the sun is converted into chemical energy in plants (photosynthesis process) When the plants dies and buried under high pressure and over millions of years it changes into fossil fuel The steam is used to turn turbines which turn generators (generators are devices used to change mechanical energy into electrical energy) Fuel chemical energy stored in fossil fuel can be released when it is burned Then the heat is used to heat water to steam. Another way to generate electricity from fossil fuel Fossil is burned inside engines the mechanical energy produced from engines is used to turn generators which produce electricity when turned 8

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11 Use the terms below to complete the sentences. Thermal Electric current Conduction Convection Energy Radiation Electrons Kinetic Potential Transformation Waste heat heat fuel Insulator conductor 1. is the transfer of thermal energy. 2. The ability to cause a change is 3. A material that is burned to produce thermal energy is. 4.. energy is the energy of motion is the transfer of thermal energy by particles bumping into each other. 6. energy is the energy of position. 7. The transfer of thermal energy that can occur only in liquid and gases is called is bundles of energy that can travel through empty space. 9. Energy changes from one form to another is called energy The energy that moves the particles of matter is called energy. 11. is the flow of electrons. 12. Unneeded thermal energy is called are the small particles inside an atom that have negative charge. 14. a.. carries electric current easily, while an does not 10

12 Circle the letter of the best choice 15. Thermal energy can be transferred by conduction from one piece of matter to another only if the two pieces are. A liquids B solids C touching D fuels 16. An object with a positive charge will attract another object with A positive B negative C no charge D all of them 17. Because there is no matter in space, thermal energy moves from the sun to Earth by.. A radiation B convection C conduction D electricity 18. When fossil fuels are burned,. energy is converted into thermal energy. A electrical B fire C matter D chemical 19. All animals convert food energy into the energy of motion and A electrical B fire C heat D chemical 20. Most energy on Earth comes from A the sun B homes C the moon D Earth 21. What two forms of energy do we receive from sunlight? A light and heat B kinetic and potential C light and wind D water and light 11

13 22. What kind of charge do electrons carry? A negative B positive C no charge D neutral 23. Electricity is basically a A movement of electrons C movement of neutrons B movement of protons D movement of cars 24. Flow of electricity is called.. A a charge B a current C heat D wind 25. What device opens and closes an electric circuit? A a power source B a switch C a conductor D a gas 26. A current needs a path to flow along which is known as.. A cloud B resistor C battery D circuit 27. If we add heat to a liquid substance, it will change into A plasma B gas C liquid D solid 28. Thermal energy is transferred from A hot to cold B cold to hot C liquid to gas D solid to liquid 29. Circle the circuit that will be dimmer. 12

14 Define the following vocabulary: 30. Electric circuit: 31. Energy: 32. Thermal energy: 33. Conductor 34. Insulator 35. Energy transformation Answer the following questions: 36. What is geothermal energy? 37. Name four energy sources. A. B. C. D.. 13

15 38. Name four uses of fossil fuel A.. B... C... D How can we use fossil fuel to generate electrical energy? 40. Why do we wear jackets in cold days? 41. How can mittens help us holding hot things? 42. Name three ways thermal energy can move. A. B. C. 43. What is waste heat? 44. What is solar energy? 45. How is thermal energy transferred from the sun to Earth? 14

16 46. What is convection? 47. What are electrons? 48. What is a charge? 49. What is electric current? 50. How is thermal energy transferred when particles are touching? Fill in the blanks to show the energy transformation in each picture In this circuit energy is converted into energy. In an iron energy is converted into energy energy is converted into energy in plants In windmills energy from the wind is converted into energy 15 In batteries energy is converted into energy

17 Complete the following map using the terms in the word bank. motion food sunlight batteries animals fuel electricity Almost all energy on Earth comes from. Which can be stored in And can be used by.. for energy And can be burned to produce heat and. And can be used to supply to toys an appliances 16

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