(Chapter 6.3) History of the Universe
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Define emission spectrum
The spectrum of frequencies of electromagnetic radiation emitted when an electron makes a transition from a high energy state to a lower energy state. As the name suggests, atoms emit energy
Define absorption spectrum
The spectrum of frequencies of electromagnetic radiation transmitted when an electron makes a transition from a lower energy state to a higher energy state. As the name suggests, atoms absorb energy
Define spectroscopy
The study of the absorption and emission of light and other radiation by matter
Define red shift
A shift in the ‘red’ of the electromagnetic spectrum and indicates the galaxy is moving away from the Earth
True or False. “Hubble correctly discovered that most galaxies tended to have a red shift.”
True
Identify the correlation between red shift and velocity
The more severe a red shift is, the higher the velocity of a galaxy
Define cosmic microwave background radiation
A faint glow of light that fills the universe, falling on Earth from every direction with nearly uniform intensity
Identify the elongated term for CMBR
The elongated term for CMBR is Cosmic Microwave Background Radiation
Outline the accepted proposed history of the Universe by the majority of society
• The universe began from a singular point containing large amounts of energy • Space and time are created from the big bang • The energy was converted into matter - atomic nuclei and clusters of protons and neutrons • Within 400 00 years, the universe began to cool until the point where it was possible for electrons to combine with the atomic nuclei to form neutral atoms • Electromagnetic radiation and CMBR entropied throughout the universe. • The universe was cool enough for gravity to clump matter and form celestial bodies
Define the Big Bang Theory
A theory that states the universe and life started from a singular hot and dense particle that expanded into the universe
Define the Steady State Theory
A theory that states the universe has always existed and always will; that the universe had no beginning and has no end. Furthermore, the expansion of the universe is caused by the constant creation of matter at an enormous rate
Define radio source
Any of various objects in the universe that emit relatively large amounts of radio waves
Recall the alternate term for radio source
Radio galaxies is the alternate term for radio source
True or False: “Each element has unique spectra lines”
True
Recall the formal term for red shift
The formal term for red shift is velocity of recession
Explain why the occurrence of red shifts supports the theory that the universe is expanding
Red shifts show that galaxies are moving away from the Milky Way; hence, the distance between galaxies is expanding, which can only be explained by the expansion of the Universe
Recall the most common element in space
Hydrogen is the most common element in space
Recall the formula for energy
E = mc^2 where: E = energy (Joules) m = mass (kg) c = speed of light (m/s)
Recall the formula for Newton’s universal law of gravitation
F = G * (m_1 * m_2)/d^2 where: F = Force of attraction (N) G = Gravitational constant (6.67*10^-11) m_1 = Mass of Object 1 (kg) m_2 = Mass of Object 2 (kg) d^2 = Distance between objects (m)
Recall the influence of gravity on the formation of the universe
Gravity formed celestial bodies