Astronomy Midterm (10/27)

suppose you know the frequency of a photon and the speed of light. what else can you determine about the photon?

its wavelength and energy

if your mass is 60kg on Earth, what would be your mass on the moon?

60 kg

the fact that Voyager 10 continues to speed out of the solar system even though its rockets have no fuel is an example of

Newton's first law of motion

what do astronomers mean by a constellation

a constellation is a region in the sky as seen from Earth

cell phone signals passing through walls is an example of

transmission

when both are viewed a distance away from Earth, would a person standing on the South Pole appear to be oriented upside down compared with a person standing on the North Pole?

Yes, but they would each believe they were standing upright

the universe is defined as

all material, space, and energy that exist: everything

when an electron drops to a lower energy level in an atom

light at a wavelength specific to the change in energy levels is emitted

why is Newton's version of Kepler's third law so useful to astronomers?

it can be used to determine the masses of many distant objects

suppose you are in an elevator that is traveling upward at a constant speed. how does your weight compare to your normal weight on the ground?

it is the same

how many arc minutes are in one degree?

60

thermal radiation

radiation with a spectrum whose shape depends only on the temperature of the emitting object

what is the evidence for the existence of the mysterious "Dark Matter"?

IDK

from shortest to longest wavelength, which of the following correctly orders the different categories of electromagnetic radiation?

gamma rays, X-rays, ultraviolet, visible light, infrared, radio

What is the ecliptic?

the path the Sun appears to trace around the celestial sphere each year

what is the longest wavelength?

10 km

Gravity is an inverse square law in distance. Therefore, if the distance between two masses is decreased by a factor of 4, the gravitational force between those two masses

increases by a factor of 16

how many arc seconds are in one arcminute?

60

where did the elements hydrogen and most helium form?

Big Bang

Sunlight tales 8.4 minutes to get from the Sun to Earth. When NASA's New Horizon Spacecraft passed Pluto in 2016, it was 33 AU from Earth. How long did it take for its transmitted imaged of Pluto to arrive at Earth?

4.6 hours

How many seconds are in one year?

about 30 million

According to the universal law of gravitation, the force due to gravity is

inversely proportional to the square of the distance between objects

The Earth has a radius of about 6,000 km. How long would it take for an object traveling at the speed of light to circle the earth?

1/8 of a second

Our solar system is located about 27,000 light-years away from the galactic center. How far does out solar system travel in one orbit?

170,000 light-years

Doppler shifted hydrogen absorption lines are seen in the spectrum of a star. The hydrogen line at 656.28 nm is seen to be shifted to 656.08 nm. Is the star moving towards or away from us, or can we not tell?

moving towards us

Red light has a lower energy per photon than blue light. Therefore, red light has

lower frequency, longer wavelength than blue light

Which is hotter

a blue star

Light takes approximately one second to travel from Earth to the moon. This means that the Moon is approximately

300,000 kilometers from Earth

what does temperature measure

the average kinetic energy of particles in a substance

What would happen if a rocket were launched with a speed greater than Earth's escape velocity?

it would travel away from Earth into the solar system

The planet Mars is, on average, about 228 million km from the Sun. How long does ti take light from the Sun to reach Mars?

about 12.7 minutes

The reason galaxies that are distant from our galaxy move away from our galaxy more rapidly than those near is

more space expands between us and the distant galaxies