the univers

Question 1

what is white light?
what happens when it passes through a prism?

Answer 1

a mixture of colours of the which all have different ranges of wavelength

when it passes through a prism the white light is split into a spectrum of colours.

Question 2

what happens when light passes through a gas

Answer 2

When white light passes through a gas of an element before passing through a prism, the spectrum produced will have a pattern of dark lines. These dark lines are called absorption lines.

Question 3

what are the black lines present in the absorption spectrum

Answer 3

this is where the gas that the light is passing through has been absorbed an emitted elsewhere

Question 4

state how a star produces an absorption spectra

Answer 4

When studying the spectra from stars, the same dark lines are present as in the absorption spectra. These lines are present because the white light produced by each star passes through the gasses in the star’s atmosphere. As the light passes through, gas atoms in a star’s atmosphere absorb specific wavelengths of visible light. The wavelengths absorbed are specific to the elements present in the star.

Comparing the pattern of lines in the Sun’s absorption spectrum to the pattern for known elements allowed scientists to work out which elements are present in the Sun’s atmosphere.

Question 5

what is the connection between the wavelength and red shift

Answer 5

the more closer the lines are to the red side the bigger their wavelength

Question 6

near galaxies have a
farther galaxies

Answer 6

small Redshift showing that they are moving away
have a bigger Redshift meaning they they are moving away faster

this provide evidence that the universe is expanding