1 00:00:00,180 --> 00:00:15,359 Energy. What is energy? Energy causes matter to change. We use it to carry out work. Plants. They take sun's energy to produce food, oxygen and to grow. 2 00:00:15,359 --> 00:00:17,379 Humans 3 00:00:17,379 --> 00:00:21,660 We use energy from food to work, play, do sports 4 00:00:21,660 --> 00:00:23,640 Industries 5 00:00:23,640 --> 00:00:27,760 They use energy to make products from raw materials 6 00:00:27,760 --> 00:00:35,899 Energy is also used in transport or to light up streets, houses 7 00:00:35,899 --> 00:00:38,740 Forms of energy 8 00:00:38,740 --> 00:00:41,179 There are many different forms of energy 9 00:00:41,179 --> 00:00:43,759 Electrical energy 10 00:00:43,759 --> 00:00:49,020 It comes from the movement of electric charges and also from other forms of energy. 11 00:00:49,759 --> 00:00:51,780 It is called electricity. 12 00:00:53,380 --> 00:00:54,579 Thermal energy. 13 00:00:55,100 --> 00:00:57,560 It is the energy in form of heat. 14 00:00:58,799 --> 00:00:59,899 Kinetic energy. 15 00:01:00,240 --> 00:01:02,820 It comes from the movement of something. 16 00:01:04,060 --> 00:01:05,200 Light energy. 17 00:01:05,879 --> 00:01:08,799 It allows us to see and travel straight away. 18 00:01:10,159 --> 00:01:11,120 Nuclear energy. 19 00:01:11,120 --> 00:01:14,299 It comes from the nucleus of an atom. 20 00:01:16,019 --> 00:01:17,159 Chemical energy. 21 00:01:17,500 --> 00:01:24,480 It is produced in chemical reactions, for example in food, water or fuel. 22 00:01:25,540 --> 00:01:26,859 Energy sources. 23 00:01:27,739 --> 00:01:29,079 There are two types. 24 00:01:31,340 --> 00:01:32,680 Non-renewable. 25 00:01:33,540 --> 00:01:34,420 Renewable. 26 00:01:35,700 --> 00:01:36,819 Non-renewable. 27 00:01:37,359 --> 00:01:40,980 They are on Earth in limited amounts. 28 00:01:41,939 --> 00:01:45,040 They run out as we use them. 29 00:01:46,980 --> 00:01:56,519 Oil. We use it as a fuel, for example in cars and to produce plastics. 30 00:01:57,739 --> 00:02:03,260 Coal. We use it to produce electricity in power plants and to make iron. 31 00:02:04,439 --> 00:02:11,099 Natural gas. We use it as a fuel to produce electricity and for cooking and heating in our houses. 32 00:02:12,419 --> 00:02:20,539 Uranium. We use this metal to produce electricity in nuclear power plants. It's very toxic. 33 00:02:22,199 --> 00:02:27,400 Renewable. We can use them as many times as we want and they do not run out. 34 00:02:28,639 --> 00:02:32,740 The sun. It gives us two types of energy. 35 00:02:34,219 --> 00:02:40,120 Light energy. It helps us to produce electricity with solar panels. 36 00:02:40,120 --> 00:02:46,120 Thermal energy. We use solar thermal collectors to heat water with it. 37 00:02:46,120 --> 00:02:57,120 Wind. Wind energy. It is the air moving. It makes kinetic energy and with the help of wind turbines we produce electricity. 38 00:02:57,120 --> 00:03:06,120 Water. Hydraulic energy. We use the water in reservoirs to move electric generators and produce electricity. 39 00:03:06,120 --> 00:03:14,120 Heat, thermal energy. It is a form of energy that moves from a hotter object to a colder one. 40 00:03:15,120 --> 00:03:21,120 There are two types of sources of heat, natural, the sun or lava. 41 00:03:22,120 --> 00:03:27,120 Artificial, a heater, a light bulb, a good fire. 42 00:03:28,120 --> 00:03:30,120 Heat can change matter. 43 00:03:30,120 --> 00:03:37,479 When an object absorbs heat, it gets warmer and expands, becomes bigger. 44 00:03:38,780 --> 00:03:43,639 Water is an exception. When it gets warmer, evaporates. 45 00:03:44,680 --> 00:03:49,740 When an object emits heat, it cools down and contracts, becomes smaller. 46 00:03:50,879 --> 00:03:58,020 Water is an exception. When it cools down, it becomes ice, which occupies more space than liquid water. 47 00:03:58,020 --> 00:04:07,680 Temperature. It is the measuring of heat in an object. We measure it with a thermometer. 48 00:04:09,360 --> 00:04:14,879 There are two types of thermometers. Analog thermometer and digital thermometer. 49 00:04:16,360 --> 00:04:21,980 Light. It is a form of energy produced by luminous objects. 50 00:04:22,980 --> 00:04:27,519 It can come from a natural object, for example, the sun. 51 00:04:28,019 --> 00:04:34,160 Or from an artificial object that needs electricity to produce it, for example, a light bulb. 52 00:04:35,399 --> 00:04:38,339 Light affects things in different ways. 53 00:04:38,660 --> 00:04:42,160 A transparent material allows all the light to pass through. 54 00:04:42,939 --> 00:04:46,939 A translucent material lets part of the light pass through. 55 00:04:48,079 --> 00:04:53,779 An opaque material does not let light pass through, and you cannot see the other side.