Formulas and Constants
Unit 2: Light
Unit 3: Telescopes
Unit 4: Stars
Unit 5: Galaxies and the Universe
100
What is the formula for the doppler effect?
v = c(∆lambda)/lambda_0
100
What happens to the energy of light as it changes from radio wave to gamma rays?
The energy increases
100
Your eye has a diameter of 0.8 cm. Your telescope has a diameter of 20 cm. How much more light does your telescope collect than your eye?
625 times more light
100
How do stars generate light and energy?
Nuclear fusion in their core
100
What type of galaxy is this?
Spiral
200
What is the formula for light gathering power and what does it tell us?
((D_1)/(D_2))^2
It tells us how many times more light one telescope can collect compared to another telescope.
200
What happens to the wavelength of visible light as it changes from violet to red?
The wavelength increases (gets longer).
200
You want to build a refracting telescope and not a reflecting telescope. This means you'll have to buy a __________.
Lens
200
What happens to the lifespan of a star as the mass of the star decreases?
The lifespan increases
200
What type of galaxy is this?
Elliptical
300
What is the speed of light in m/s?
c = 3 x 10^8
300
What color of visible light has a wavelength of 600 nm?
Orange
300
What is an atmospheric window?
The range of light wavelengths that can pass through the atmosphere and reach the ground.
300
How do we use an H-R diagram to tell whether a star cluster is young or old?
Younger star clusters have more spectral classes present and older star clusters have fewer spectral classes present.
300
In which kind(s) of galaxy would we expect to see a supernova?
Spirals and Irregular galaxies since they have high-mass stars.
400
What is the formula for resolution?
R = (252,000* lambda)/D
400
Which spectrum is continuous?
Spectrum C
400
If we want to build a telescope that detects infrared light, where should this telescope be placed?
In space
400
Is the Sun going to explode at the end of its life?
No, the Sun is a lower-mass star and will end its life as a planetary nebula and white dwarf.
400
What does it mean that the light from galaxies is redshifted?
They are moving away from us and the universe is expanding.
500
What is the formula for telescope magnification?
M = (F_O)/(F_e)
500
Which star is the dimmest?
Star A
500
Which telescope can see smaller details:
Telescope 1 with a resolving power of 0.70"
Telescope 2 with a resolving power of 1.80"
Telescope 1
500
When a star goes supernova, why do its outer layers explode outward if the core collapses inward?
The outer layers of the star rebound (bounce) off the core when the core suddenly stops collapsing. This causes the outward explosion.
500
How would the age of the universe be impacted if the Hubble Constant was larger than 70 km/s/Mpc?
It would mean that the universe is expanding faster than we thought and that the universe is younger than we thought.
600
What is the formula for the Schwarzschild Radius of a black hole?
R = (2GM)/(c^2)
600
A star's light is shifted from 656 nm to 657.1 nm. Is this a redshift or blueshift, and how fast is this star moving?
This is a redshift and the star is moving at a velocity of 503,048.78 m/s away from us.
600
Calculate the magnification achieved by this combination of lenses:
Objective Lens focal length = 30 cm
Eyepiece Lens focal length = 5 cm
This combination of lenses will make the image appear 6 times bigger.
600
Calculate the Schwarzschild Radius of a black hole for an object with the same mass as Earth.
M_(Earth) = 5.97*10^24kg
R = 0.0088 m
600
Are we at the center of the universe?
Yes and No! We are at the center of our observable universe, but there is no center to the actual whole universe.