EM Waves & Atoms
- Atoms can interact with electromagnetic (EM) waves in one of two ways, they can be:
- Absorbed
- Emitted
- When an EM wave hits an atom, it can be absorbed by one of the electrons giving it energy
- This causes the electron to move up to a higher energy level
- If an electron moves down to a lower energy level it will emit an EM wave in the process
- In this way, atoms can absorb and emit electromagnetic waves over a wide range of frequencies
The electrons orbiting atoms can absorb and emit EM waves by moving between different energy levels
- The energies associated with electron transitions tend to be in the visible and ultraviolet range (and sometimes X-rays)
- Higher energies (ie. gamma rays) can only be achieved when EM waves interact with the nucleus
- The nucleus of an atom can absorb and emit EM waves in a similar way to electrons
