high energy em waves, radio waves and atoms

how can atoms interact with em waves?

absorbed or emitted

what happens when an em waves hit an atom?

the em wave can be absorbed by an electron, gaining energy and causing the electron to move up an energy level

what happens when a electron moves down an energy level?

it will emit an EM wave

how can a change to the nucleus cause emission of EM waves?

gamma waves can be emitted from radioactive nuclei, and that nuclei then has less energy than it had at the start

which waves are potentially hazardous to the human body?

UV, X-rays and gamma

what is the risk of UV to the human body?

increases risk of skin cancer and aging of skin

what do X-rays and gamma rays do?

they are ionising, and can kick electrons off atoms when they are absorbed. so they can cause gene mutation, and therefore risk of cancer

what is the dose of radiation?

a measure of the risk of harm resulting from an exposure of the body to ionising radiation

how are radio waves produced?

when electrons oscillate back and forwards in electrical circuits in an alternating current

what determines the frequency of the radiowaves?

the oscillation of the charge is the same as the frequency as the radio waves produced

what can absorb the radio waves from a transmitter?

an aerial

what does the aerial do?

absorbs the radio waves, and creates an alternating current with the same frequency as the transmitted radio waves