Solar System Flashcards
(31 cards)
What does the universe consist of ?
Billions of galaxies, which contain billions of stars
What does the solar system consist of?
The sun (a star), planets in orbit around the sun, satellite moons, comets and asteroids
Order of planets
Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune
What helps keep everything in orbit
The suns gravity
What are asteroids?
Rocky objects orbiting the sun in the asteroid belt
What are meteors ?
Tiny chunks of rock moving through the solar system
Orbital speed equation
Orbital speed = distance / time
How do all objects stay in their orbit?
Gravitational force
What does the gravitational field strength depend on?
Mass and radius
The further away the galaxy….
The greater the red-shift
What are spectral likes due to?
Elements present in stars (mostly hydrogen)
Equation to calculate how fast a galaxy is moving
Change in wavelength / reference wavelength = velocity of galaxy /speed of light
What did Hubble calculate?
The recession speeds for many galaxies and compared them to distance they were from us
What did Hubble find out?
The further away a galaxy, the faster it is moving away
Speed and distance are proportional
He concluded that the universe must be expanding
Big Bang theory
1) every galaxy in the universe moves away from every other galaxy as it expands
2) therefore the galaxy must have been smaller previously
3) implies it started at a single point called a Big Bang
4) 14 million years ago
Another piece supporting Big Bang theory
The discovery of the cosmic microwave background radiation
Explain the CMBR
When the universe formed, short wavelength electromagnetic radiation existed through space
As the universe expanded, the wavelength increased, until now when it is in the microwave region
Explain the electrostatics of a plastic rod and cloth
1) initially uncharged rod and cloth
2) friction causes negative charges to move from rod and cloth
3) rod becomes positive
4) cloth becomes negative
Only negative…..
Ever move
Can metals be charged by friction?
No
Like charges….
Repel
Opposite charges….
Attract
What is the elastic region?
The region where the extension and force are proportional
What does hooke’s law state
The force is directly proportional to the extension, in the elastic region
