https://padlet.com/amckee813/fojocofiic86 Made with the help of a typing monkey en-us 2017-10-16 09:22:04 UTC 2023-03-23 01:26:56 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/Lightdecrease.png amckee813 https://padlet.com/amckee813/fojocofiic86/wish/197260844 All electro magnetic waves have the following properties:  
1. they are all  transverse
2.  they all can travel through a vacuum 
3. they all travel at the same speed in vacuum ]]> 2017-10-16 09:28:44 UTC https://padlet.com/amckee813/fojocofiic86/wish/197260844 amckee813 https://padlet.com/amckee813/fojocofiic86/wish/197261269 Electro magnetic waves also show properties which are common to all waves such as: 
1. they all move energy from one place to another
2.  they all obey the wave equation        ( velocity = frequency x wavelength)
3. they can be reflected and refracted ]]> 2017-10-16 09:30:49 UTC https://padlet.com/amckee813/fojocofiic86/wish/197261269 chamill740 https://padlet.com/amckee813/fojocofiic86/wish/197267989 Radio waves have a wavelength that ranges the whole way from metres to kilometres. They are quite low in both energy and frequency. They are used for the transmission of TV and radio and for communication between police and ambulances.]]> 2017-10-16 10:04:23 UTC https://padlet.com/amckee813/fojocofiic86/wish/197267989 amckee813 https://padlet.com/amckee813/fojocofiic86/wish/201656643 We can only see waves with a length of between 300 and 700 nanometres. The uses are vision, photography and for optical fibre communications. ]]> 2017-10-30 11:11:46 UTC https://padlet.com/amckee813/fojocofiic86/wish/201656643 amckee813 https://padlet.com/amckee813/fojocofiic86/wish/201657853
All hot objects emit infrared. the higher the temperature the more radiation it emits. Infrared can be uses for heating- toasters and grills, Night vision equipment and astronemers use it to obtain information about the temperature of stars. ]]> 2017-10-30 11:18:19 UTC https://padlet.com/amckee813/fojocofiic86/wish/201657853 amckee813 https://padlet.com/amckee813/fojocofiic86/wish/201660059 gamma rays have a wavelength of 0.0001 nano meters. gamma rays are used to kill cancerous cell in a process called radiotherapy. They are also used in the food industry to treat fresh fruit with to increase their shelf life. However theses waves can cause cancer. ]]> 2017-10-30 11:26:47 UTC https://padlet.com/amckee813/fojocofiic86/wish/201660059 amckee813 https://padlet.com/amckee813/fojocofiic86/wish/201663791 x-rays are most commonly known for medical diagnosis, xray photographs allow broken bones to be identified. They are however used for medical therapy. x-rays can unfortuantley damage cells and casue cancer]]> 2017-10-30 11:43:08 UTC https://padlet.com/amckee813/fojocofiic86/wish/201663791 chamill740 https://padlet.com/amckee813/fojocofiic86/wish/205498982 Microwaves are used for cooking food. The microwaves are absorbed by water molecules in the food which causes them to vibrate and cook the food. Microwaves are also used in radar to detect the position of aircraft, missiles and ships]]> 2017-11-09 20:33:15 UTC https://padlet.com/amckee813/fojocofiic86/wish/205498982 chamill740 https://padlet.com/amckee813/fojocofiic86/wish/205502823 The ultraviolet part of the spectrum ranges from x10^-7m  down to x10^-9m. Ultraviolet radiation is used to identify forgeries of bank notes and to kill bacteria in hospitals and hotel kitchens. Exposure to large amounts of UV radiation is dangerous however as it can damage the eyes and cause skin cancer]]> 2017-11-09 20:44:41 UTC https://padlet.com/amckee813/fojocofiic86/wish/205502823