Physics P1.6

P1 6.1

Electromagnetic radiations travel as waves and carry information and energy.

All electromagnets can travel through a vacuum at the same speed but have different frequencies.

All of these waves are on the electromagnetic spectrum. The furthest to the left is the waves with the lowest frequencies and highest wavelengths. 

All electromagnetic waves can travel at [3 x 10(to the power 8) m/s]. Therefore we can use the equation v = f x wave length (as learned earlier) to calculate the frequency or wavelength.

P1 6.2

Our eyes detect visible light and we can see the different wavelengths of colours, thus allowing us to distinguish between them.

All objects emit radiation. The hotter an object, the more IR it emits.

Microwaves are used in satellite television and mobile phone connections. Microwaves are strong enough to leave the Earth's atmosphere, which allows us to get SATELLITE television.

Radiowaves are not strong enough to leave the Earth's atmosphere, therefore are only used for communications (including emergency communications). 

The microwaves and radio waves' radiation can be absorbed by body tissue and can damage internal organs. 

P1 6.3

When an "alternating voltage" is attached to…