Doppler Effect/Red Shift/Blue Shift

Front

What does it mean when we say the universe is expanding?

Back

It means that all of the galaxies are spreading out or moving apart.

Front

What does a red shift in light indicate about a star's movement relative to Earth?

Back

It indicates that the star is moving away from the Earth.

Front

What does a blue shift in light indicate about a star's movement relative to Earth?

Back

It indicates that the star is moving towards the Earth.

Front

What is the term used to describe the shift in wavelength when objects move away from an observer?

Back

Red Shift.

Front

What is the Doppler effect in relation to light?

Back

It is the change in wavelength (or frequency) of light from an object moving relative to an observer.

Front

What happens to the wavelengths of light when an object emitting light moves away from an observer?

Back

The wavelengths of light are stretched out, resulting in a red shift.

Front

What happens to the wavelengths of light when an object emitting light moves towards an observer?

Back

The wavelengths of light are compressed, resulting in a blue shift.

Front

How does the Doppler effect apply to sound waves?

Back

Similar to light, sound waves compress when the source moves towards an observer (higher pitch) and stretch when it moves away (lower pitch).

Front

What is the significance of red shift in the context of the universe?

Back

Red shift provides evidence for the expansion of the universe and supports the Big Bang theory.

Front

What is the relationship between red shift and the distance of galaxies?

Back

Generally, the greater the red shift, the farther away the galaxy is from the observer.