CP 5 Reading Messages from the Cosmos Flashcards
Definition of energy
is the ability to do something (usually denoted as “work”).
Energy is mesured in:
Joules
Define power
Energy used or produced per time
Power is measured in
Watt
what is 1 Watt in joules
1 Joule per second
How do light and matter interact
- Emission
- Absorption
- Transmission
– Transparent objects transmit light.
– Opaque objects block (absorb) light. - Reflection/scattering
What is light
Light can act either like a wave or like a
particle
what are particles of light called
Particles of light are called photons
what is a wave
A wave is a pattern of motion that can carry energy without carrying matter along with it
define wavelength
Wavelength is the distance between two wave peaks
define frequency
Frequency is the number of times per second that a wave vibrates up and down
TF each photon has a wavelength and a frequency
T
Define istope
Isotope: same # of protons but different # of
neutrons
What are the 4 phase changes
Ionization
Dissociation
evaporation
melting
what is ionization
atoms into plasma
what is dissociation
molecules into atoms
what is evaporation
liquid into gas
what is melting
solid into liquid
what does the phase depend on
temperature and pressure.
what are the three types of spectra
Emmission line
continuous
absorption line
what is continuous spectrum
The spectrum of a common light bulb spans all visible wavelengths (everything u can see)
what is an emmission line spectrum
emits light only at specific wavelengths, producing a spectrum with bright emission lines
what is absorption line spectrum
absorb light of specific wavelengths,
leaving dark absorption lines in the spectrum
TF Each type of atom has a unique set of
energy levels
T
TF Only humans emit thermal radiation
F (Nearly all large or dense objects emit thermal radiation, including stars, planets, you)
TF Hotter objects emit less light per area at all frequencies
F Hotter objects emit more light per area at all frequencies
