Electromagnetic Wave Practicals
One of the uses of UV radiation is a security feature of bank notes. Shining UV radiation on to the bank note causes them to fluoresce (the atoms in the material take in the UV radiation and re-emits it as light which we can see)
Look at how advanced the fluorescing shapes and colours are.
IR cameras are used by the police to track for criminals at night but they are also really useful to the fire brigade at finding people in smoked filled buildings, you can’t hide behind a bin bag and even a hand print can leave a “heat print”.
Did you know you can be on the radio? Not very musical but it can drown out Radio Scotland.
The electromagnetic (em) spectrum is a collection of transverse waves that all travel at the same speed in air, the speed of light, 300 000 000 m/s. (equivalent to 7.5 times round the Earth every second)
One of the waves is VISIBLE LIGHT
Others are RADIO & TV, MICROWAVE.
The others are INFRA-RED, ULTRA VIOLET, X-RAYS, GAMMA WAVES.
The only difference between each of these waves is their wavelength or frequency. They all fit the formula
Speed= frequency × wavelength
The order is important and to remember it use the following rhyme!
Randy Radio & TV
Period, T, is the time for one wave to pass a point and is measured in seconds.
Frequency, f is the number of waves being produced or passing a point per second. Frequency is measured in Hertz (Hz)
Here are lots of resources for you to check and practice. My utmost apologies if I have not credited people for sending this material. As soon as I know who you are I will thank you personally.