1 00:00:01,199 --> 00:00:17,149 light and electricity what is light light is a form of energy that illuminates things 2 00:00:17,149 --> 00:00:25,609 it is visible by particles called photons where is light light is everywhere life could not exist 3 00:00:25,609 --> 00:00:33,570 without light light is visible to the human eye it is believed to travel faster than anything in 4 00:00:33,570 --> 00:00:39,250 the universe it travels through liquids and gases too there are two main types 5 00:00:39,250 --> 00:00:45,210 of light natural light and artificial light natural light can be found in 6 00:00:45,210 --> 00:00:52,469 nature it is not electronic artificial light is human-made electricity how can 7 00:00:52,469 --> 00:00:58,009 we change light light travels in a straight line but there are three ways 8 00:00:58,009 --> 00:01:05,629 to change light. The first is through reflection. Reflection occurs when light 9 00:01:05,629 --> 00:01:13,250 waves bounce off a surface. You can also change light through refraction. 10 00:01:13,250 --> 00:01:22,159 Refraction is the bending or turning of light changing its path. The third way to 11 00:01:22,159 --> 00:01:27,760 change light is by blocking it. Blocked light is when light is blocked by a 12 00:01:27,760 --> 00:01:39,000 a non-transparent object. But what is electricity? Electricity is a transfer of electrons from one 13 00:01:39,000 --> 00:01:45,879 atom to another. Electrons move and create an electric current which allows light to shine. 14 00:01:47,480 --> 00:01:52,760 The current flows through electrical wires and powers electronic items. 15 00:01:52,760 --> 00:02:01,579 Here are two types of electricity. Static electricity is generated by rubbing two or 16 00:02:01,579 --> 00:02:09,199 more objects together to build friction. There is also current or dynamic electricity. This 17 00:02:09,199 --> 00:02:15,259 is generated by the flow of an electrical charge through a conductor across the electrical field. 18 00:02:15,259 --> 00:02:24,419 Electronics need an electrical current to operate. Electric current travels through wires, 19 00:02:24,419 --> 00:02:31,919 which can either be a direct or alternating current direct current is 20 00:02:31,919 --> 00:02:38,639 the power that comes from batteries fuel cells or solar cells there are positive 21 00:02:38,639 --> 00:02:47,500 and negative terminals the electrons travel in one direction next there is 22 00:02:47,500 --> 00:02:52,780 alternating current this is the power that comes from power plants which 23 00:02:52,780 --> 00:02:55,020 to travel through power lines. 24 00:02:55,020 --> 00:02:58,539 This current reverses or alternates 25 00:02:58,539 --> 00:03:02,159 between the plant and the destination of the power. 26 00:03:02,159 --> 00:03:05,039 The electrons travel in a loop. 27 00:03:06,280 --> 00:03:09,020 There are many ways to provide energy. 28 00:03:09,020 --> 00:03:11,219 The first is through magnetism. 29 00:03:11,219 --> 00:03:15,800 Magnetism is electricity that can be produced by magnets. 30 00:03:15,800 --> 00:03:21,960 This is because a magnetic field can move electrons. 31 00:03:21,960 --> 00:03:26,219 Power plants use giant magnets to create electricity 32 00:03:26,219 --> 00:03:27,900 by using generators. 33 00:03:29,240 --> 00:03:32,879 Power plants provide the energy for the alternating current 34 00:03:32,879 --> 00:03:36,280 flowing in both directions through the power lines. 35 00:03:38,180 --> 00:03:40,879 When you turn on a light in your home 36 00:03:40,879 --> 00:03:44,219 or plug something into an electrical outlet, 37 00:03:44,219 --> 00:03:49,610 the power flows from the power plant. 38 00:03:49,610 --> 00:03:52,310 However, before it enters the home, 39 00:03:52,310 --> 00:03:58,729 will pass through the transformer on the utility pole. Then it travels from the 40 00:03:58,729 --> 00:04:04,189 circuit breaker or fuse box to the outlets and wall switches you use in 41 00:04:04,189 --> 00:04:10,370 your home. There are different fuels used by power plants to produce electricity 42 00:04:10,370 --> 00:04:19,329 across the world. Thermal power plants have two different categories. Nuclear 43 00:04:19,329 --> 00:04:25,089 power plants that create electricity by burning fuel and electric power plants 44 00:04:25,089 --> 00:04:32,589 that create electricity via prime mover. There's also solar power plants. Solar 45 00:04:32,589 --> 00:04:39,389 power plants make use of the available solar energy from the Sun. Lightning, 46 00:04:39,389 --> 00:04:48,129 conductors, and insulators. Lightning is electricity. It is an electric current 47 00:04:48,129 --> 00:04:55,029 found in nature. Lightning occurs when small bits of ice collide inside of a 48 00:04:55,029 --> 00:05:00,370 cloud. That creates an electric current and when it interacts with the ground, 49 00:05:00,370 --> 00:05:10,310 lightning strikes. Conductor. A conductor is any material or substance that allows 50 00:05:10,310 --> 00:05:16,589 electricity to flow through them. Examples are metals like steel, copper, 51 00:05:16,589 --> 00:05:27,790 iron, gold, and silver. Seawater can also be a conductor. Insulators. Insulators prevent or 52 00:05:27,790 --> 00:05:38,339 block the flow of electricity. Examples include plastic, rubber, glass, and porcelain. Thomas 53 00:05:38,339 --> 00:05:47,819 Alva Edison, 1847 to 1931. A poor and shy boy, nearly deaf due to sickness, Edison learned to 54 00:05:47,819 --> 00:05:54,480 conduct experiments with his mother. By the age of 15, Edison got his first job as a telegraph 55 00:05:54,480 --> 00:06:03,439 operator. His first major invention was a volt counter. Thomas Edison's first big project 56 00:06:03,439 --> 00:06:14,759 was an improved stock ticker. It sold for $40,000. In 1878, Edison came up with a major 57 00:06:14,759 --> 00:06:20,519 improvement on the light bulb he helped create the first electric power station to generate 58 00:06:20,519 --> 00:06:28,600 electricity in two homes thomas edison was a man of many inventions here are a few of his 59 00:06:28,600 --> 00:06:38,120 inventions and advancements the phonograph completed in 1877 it was made to record and 60 00:06:38,120 --> 00:06:48,730 play sound using a metal needle. Next is the kinetograph made in 1861. The kinetograph is 61 00:06:48,730 --> 00:06:57,449 the first motion picture camera. Next is the incandescent light bulb 1879. Edison did not 62 00:06:57,449 --> 00:07:04,329 invent the first light bulb but he did complete the first commercially viable one. 63 00:07:04,329 --> 00:07:12,470 Thomas Edison made major improvements on x-ray technology, batteries, and telephones as well. 64 00:07:13,209 --> 00:07:14,949 Thank you for listening. Goodbye.