The Doppler Effect, & also Brightness (Abs./App. Magnitude)

How does the Doppler Effect explain observations of the in the universe?

• Almost all Galaxies make lots of sound waves.

• Almost all Galaxies are moving toward us.

• Almost all Galaxies are moving away from us.

• No connection. Light waves aren't visible in the universe.

What do the light waves of a galaxy that is moving AWAY from us look like?

• red shifted
• blue shifted
• green shifted
• yellow shifted

Tags

NGSS.HS-ESS1-2

What do the light waves of a galaxy that is moving TOWARD us look like?

• red shifted
• blue shifted
• green shifted
• yellow shifted

Tags

NGSS.HS-ESS1-2

When light from the galaxy in Andromeda is analyzed, it is found that the wavelengths are shorter than expected. This tells us that the galaxy is

• moving towards us

• moving away from us

• a very distant galaxy

• rotating on its axis

The wavelength of a line in the spectrum produced by a distant star is found to be shorter than the wavelength of the corresponding line in the spectrum produced by the Sun. This is because the distant star is

• cooler than the Sun
• hotter than the Sun
• moving away from the Earth
• moving towards the Earth

When light from a distant star reaches us on Earth, its wavelength appears shifted towards the red end of the spectrum. This is because

• the distance travelled by each successive wave has increased

• the frequency of the light emitted has decreased

• the speed of the star has increased

• the star is emitting different wavelengths than it used to.

Use the image to identify the motion of the star relative to Earth. The bottom picture shows the spectrum of light from Earth if there were no movement. The top picture shows the spectrum of light from a star giving off the light. What does the top spectra show that the star is doing?

• It is moving towards the Earth.

• It is moving away from Earth.

• It is not moving relative to Earth.

• It has a larger amplitude.

• It is brighter.

Use the image to identify the motion of the star relative to Earth. The bottom picture shows the spectrum of light from Earth if there were no movement. The top picture shows the spectrum of light from a star giving off the light. What does the top spectra show that the star is doing?

• It is not moving relative to Earth

• It is moving away from Earth.

• It is moving towards Earth.

• It is brighter.

• It has a greater amplitude.

Use the image to identify the motion of the star relative to Earth. The bottom picture shows the spectrum of light from Earth if there were no movement. The top picture shows the spectrum of light from a star giving off the light. What does the top spectra show that the star is doing?

• It is dimmer

• It is Redshifting.

• It is Blueshifting.

• It has a smaller amplitude.

• It is not moving relative to Earth.

Use the image to identify the motion of the star relative to Earth. The bottom picture shows the spectrum of light from Earth if there were no movement. The top picture shows the spectrum of light from a star giving off the light. What does the top spectra show that the star is doing?

• It is not moving relative to Earth

• It is moving away from Earth (Redshift)

• It is moving towards Earth (Blueshift)

• It is moving towards Earth (Redshift)