science y10s2 Flashcards
(29 cards)
The big bang theory
around 13.8 billion years ago the entire universe was contained in an unimaginably hot, dense point and has expanded to form today’s universe
Evidence for big bang theory
Redshift
cosmic microwave background radiation
nucleosynthesis
Redshift
galaxies moving away from us appear red because red has the longest wavelength of visible light so it travels the furthest. an expanding universe proves that galaxies are still in movement after the big bang
cosmic microwave background radiation
microwaves can be detected everywhere in the universe as this is leftover energy from the big bang
nucleosynthesis
there is an abundance of H and He in the universe as these were the initial elements formed in the big bang
the doppler effect
something moving away looks or sounds different than if it is moving closer to you because of the apparent difference of frequencies.
distant galaxies appear red as they are moving away. this is called REDSHIFT
telescope and discoveries
James Webb Telescope
Discoveries:
Stephan’s Quintet
Carbon dioxide on an exoplanet
Stephan’s Quintet
a compact galaxy group
discovered with infrared light radiation
told us how galaxy evolution occurs
co2 on an exoplanet
evidence of carbon dioxide on an exoplanet
discovered by observing the atmosphere of a planet
study of its origin and evolution taught us that planets may move across galaxies
life cycle of low-mass star
nebula
low mass protostar
low mass star STABLE FUSION PERIOD
HYDROGEN USED UP
red giant
HELIUM FUSION STOPS
planetary nebula
white dwarf
black dwarf
life cycle of high-mass star
nebula
high mass protostar
high mass star STABLE PERIOD
HYDROGEN USED UP
supergiant
HELIUM FUSION STOPS
supernova
black hole OR neutron star (depends on size)
fusion processes of a low-mass star
STABLE PERIOD when it is a star
HYDROGEN RUNS OUT so turns to a red giant
HELIUM FUSION STOPS so planetary nebula.
fusion processes of high mass star
STABLE PERIOD when it is a star
HYDROGEN RUNS OUT so turns to a
supergiant
HELIUM FUSION STOPS so supernova
hertsprung russel diagram
luminosity vs temperature
look at pic and learn it!
relationship between current, volatge and resistance
the current is directly proportional to voltage and inversely proportional to the resistance.
ohms law
voltage = current x resistance
v I R
current
how many electrons pass a point in a circuit in a specified time
linear relationship between current and voltage
resistance
something which slows the flow of electrons (current) in a circuit
voltage
the pressure applied to electrons to make them move
series circuit
—x——-x———
l l
l x
l——–l i l i——–l
same current throughout
voltage divided between components
parallel circuit
——-x——–
l l
——-x——–
l l
——-x——–
l l
—–l i l i——
components in separate branches
current divided between branches
each branch uses full voltage
5 ethical frameworks
utilitarian approach
rights approach
fairness of justice approach
common good approach
virtue approach
utilitarian approach
greatest balance of good over harm
rights approach
protects ethical rights of thise affected
