ASTA01H3 Lecture 19: lecture 19
Document Summary
Meteoroids: meteors are less 100m diameter, smaller meteors are fragments of comets, very old 4. 4 to 4. 6 billion years old. Spectroscopy lines: emission lines: multiple single frequencies emitted by particular atoms. Luminous solid, liquid or dense gas produces continuous spectrum. Low density hot gas produces emission spectrum. Continuous spectrum incident on coo, thin gas produces absorption spectrum. See diagram: formation of spectral lines, when atom absorbs energy it becomes exited and electron, emission energy correspond to energy differences between jumps to an excited level from ground state allowed levels. Allowed energies are said to be quantized only certain values are allowed: energy is released in for of light, light is wave and particle. Related by the fact that frequency of the wave gives energy of the particles. Light particles each have energy e: e = hf, h is planck"s constant 6. 63x10-34 j/s, note blue light is more energetic than red. Absorption boosts the electron to second level.