Astronomy: A Beginners Guide to the Universe - Chapter 2

Electromagnetic radiation

Travels through space in form of waves

Electromagnetic waves

Disturbance that transfers energy from one place to another. Produced by accelerating charged particles . Propagation of oscillation of couples electric and magnetic fields

Wave period

Number of seconds needed for wave to repeat itself

Wavelength

Number of meters needed for wave to repeat itself

Amplitude

Maximum departure from undisturbed space

Frequency

Number of wave crests passing any given unit of time

What's the wavelength of the visible spectrum?

Between 4x10^-7m and 7x10^-7m

Relationship between colour and frequency

Colour determined by frequency

Relationship between temperature, particle vibrations, and energy radiated

Temperature <-> particle vibration <-> energy radiated

Intensity

Strength or amount of radiation

Blackbody Curve

Represents spread of intensity of electromagnetic radiation emitted across electromagnetic spectrum [depends only on temperature of object]

Effect of temperature on blackbody curve

Curve shifts towards higher frequencies (shorter wavelengths) and greater intensities as temperature increases [SHAPE OF CURVE REMAINS THE SAME]