unit 5 topic 3 Flashcards
what did Isaac Newton discover?
if you pass a beam of light through a prism it produces a spectrum of colors
what is a spectroscope
is the study of how a spectrum, produces a focused spectrum
who was Joseph von Fraunhofer and what did he observe?
he used a spectroscope to observe the spectrum produced by the sun. He noticed dark lines, called spectral lines, but didn’t know what they meant. he found these spectral lines throughout the solar system
when was the significance of the spectral lines discovered
it was discovered 50 yrs later, when Kirchoff and Bunsen, two chemists used a spectroscope to observe various chemicals when they were heated. Each specific element had its own unique spectral lines. This led to the science of spectroscopy.
What is spectroscopy?
the study of spectra as a part of chemistry.
what is diffraction grating?
instead of splitting light using spectroscope or prisms diffraction grating uses thousands of closely spaced slits to produce much better detail in the spectrum it produces
why do we see a rainbow spectra on a CD?
it is produced because the grooves on a CD act as diffraction gratings
how do astronomers determine what a star is made of?
refract the light from distant starts to determine what the star is made of
what do stars have that makes them distinct?
they have dark bands in distinct sequences and thicknesses on their spectra. Each elemnt tht is present in the star created its own black-line fingerprint.
what is a spectral analysis
is where you compare the spectra of the star to the spectra of elements to determine what elements the star is composed of.
what is the doppler effect
a change in the pitch (frequency) of sound waves because they are stretched or squeezed is known as the Doppler effect
what colors show on the spectrum when a star is approaching earth ?
it will be blue shifted
what colors will show on the spectrum when the star is moving away from the earth?
red shifted
what does the amount of shift show on a spectrum?
indicates the speed at which the star is approaching or moving away.
what is one tool that uses the doppler effect
a radar gun
