electromagnetic waves

• what are the electromagnetic waves 


  radio waves, microwaves, inferred, visible light, ultraviolet, x-rays and gamma rays
• electromagnetic waves are transverse, transfer energy from source to absorber and all travel at the same velocity through a vacuum or through air
• radio waves are used to broadcast tv as they are easily produced and detected using aerials and electronics
• microwaves are used for cooking as water molecules absorb one particular frequency of microwaves
• infrared is used in remote controls as it is easily produced using LED's
• visible light is used for photography
• ultraviolet is used for sun tanning as the ultraviolet causes a response in the skin to protect it causing it to darken.
• x-rays are used for medical imaging as x-rays pass through low density materials but is absorbed by high density materials. (showing bones of in images)
• gamma rays are used for medical treatment as it ionises atoms in cells and damage the cells/ unhealthy cells (can still damage healthy ones)
• what are the hazardous waves and why


  ultraviolet, x-rays and gamma rays are hazardous as they are ionising waves. this can damage cells in your body.
• gamma rays originate from changes in the nucleus