Rainie – what a question! I thought I would start by presenting my team with the question….
Rainie it’s all about electricity. Think about the ‘stuff’ that comes from batteries that makes your watch work or makes a torch light up the world. Electricity travels from place to place by travelling through things that allow it to travel through. It cannot travel through paper, plastics, stones and other things. It can however travel through water, some special glass, metals and you.
When you touch the screen of your telephone, you are allowing a very small amount of electricity to travel from the glass to you. The phone recognises this and knows where you have touched the screen. It then responds to the touch.
An experiment – touch the screen using a variety of materials on your finger. Try a damp finger, a finger covered by cloth, paper, aluminium foil, plastic and maybe a leaf. I am sure you can think of other materials. This little experiment might lead to other questions so please ask them.
Remember Rainie do not under any circumstances play or experiment with mains electricity. It could hurt you badly.