Cold, low density gas sits in between you and a bright source. What do you see? Continuum O Absorption lines O Perfect blackbody radiation X-rays Emission lines What was significant about the photoelectric effect? It reintroduced the particle nature of light through the existence of the photon O It explains why stars emit light across the electromagnetic spectrum It was a brand new energy generation technique It led to Newton receiving the Nobel Prize O It demonstrated the wave nature of light by showing its connection to electricity Why is it important to study the spectral lines of a hydrogen atom? O Hydrogen's energy levels are well understood and offer a good reference to study the spectral lines of other, more complex elements. All of these Hydrogen is overall positively-charged, so it represents the average atom well Hydrogen has many neutrons, which gives it a unique energy level structure Hydrogen is not subject to the confusing science of quantum mechanics How do astronomers determine the composition of distant objects? O Peak of blackbody curve Position in the sky Amount of Doppler shift Presence of spectral lines O Intensity of emission