PHYSICS TEST
WAVES
REFLECTION
astrophysics
big bang theory
transverse
longitudinal
wave equation
amplitude, peak\crest, Lambda, trough
Solar system
Satellites
Cycle of a star
compression, refraction
one full cycle is one full wave (a circle), where the same movements again
Speed of a wave (V) = frequency (f) x wavelength (L)
amplitude: maximum displacement from the rest position (is always positive)
wavelength: the distance from one peak or trough to another
frequency: number of full waves that passes your eye in one second (f), measured in Hz (hertz)
Period (T) = 1\frequency (f)
mirror and normal are perpendicular. incoming\incident ray and reflected ray are opposite. Angle of incidence (angle between the ray and normal, i=r)
the image is virtual (not real). the distance is the same always the same
nebulae : collection of gas, rocks and dust
protostar : gravity slowly pulls together the particles, energy converted into heat
main sequence : gasses are created and pull outwards but grafvity keeps it together
red giant: hydrogen and helium gass, cold and red. can be a super giants grow bigger and bigger
death: small stars collapse and become a white dwarf --> then black dwarfs. supergiants explodes and creates a supernova. if the star is big enough it become a black hole.
The big bang is how astronomers explain the way the universe began. It is the idea that the universe began as just a single point, then expanded and stretched to grow as large as it is right now (its theory includes that the big bang is still expanding right now)
This extremely dense point exploded with unimaginable force, creating matter and propelling it outward to make the billions of galaxies of our vast universe
made of one star (the sun) plus 8 planets + dwarf planet
small part of the Milky way galaxy
Mercury Venus Earth Mars Jupiter Saturn Uranus Npetune Pluto
friction heats the gases until its hot enough for nuclear fusion to happen
FUSION combination of lighter isotopes of hydrogen to form helium
gravitty act inwards and fusion acts outwards.
can be natural or arttificial
geostationary: orbit the earth once every 24 hours, are used for communications
monitoring, weather, orbit every 2-3 hours
red shifted from far away, cosmic microwave background radiation
click to edit