Absorbing and emitting Electromagnetic waves

All electromagnetic waves travel at the speed of light, and can travel through a vacuum

Radio emitted when

Electrons oscillate in a conductor (transmitter)

Radios absorbed when

Electrons oscillate in a conductor (aerial)

Microwaves emitted when

Electrons oscillate in a conductor (transmitter)

Microwaves absorbed when

Electrons oscillate in a conductor (aerial) and molecules rotate

Infrared emitted when

Atoms vibrate and lose kinetic energy

Infrared absorbed when

Atoms vibrate and gain kinetic energy

Visible light emitted when

Electrons fall from high energy level to low energy level

Visible light absorbed when

Electrons jumper from low energy level to high energy level

Ultraviolet emitted when

Electrons fall from higher energy level to lower energy level

Ultraviolet absorbed when

Electrons jump from lower energy level to much higher energy level. High energy UV may cause ionisation

X-rays emitted when

Fast moving electrons collide with a metal target. Electrons lose kinetic energy

X-rays absorbed when

Electrons in atoms gain energy and leave the atom completely (ionisation)

Gamma rays emitted when

Radioactive decay of radioactive nuclei. Nuclear processes in star

Gamma rays absorbed when

Electrons in atoms gain energy and leave the atom completely (ionisation)