Hydrogen gas is placed in a glass discharge tube in a laboratory. An emission spectrum is produced.
Complete the sentences to explain the cause of the lines in the emission spectrum.
Use words from the list:
atoms, electrons, neutrons, photons, protons
...................................... transition from a higher energy level to a lower energy level and emit ...................................... .
There is a potential difference of 6200 V6200\text{ V}6200 V across the discharge tube.
A charge of 0.15 C0.15\text{ C}0.15 C flows through the gas.
Calculate the energy transferred.
Use the equation: energy transferred=charge×potential difference\text{energy transferred} = \text{charge} \times \text{potential difference}energy transferred=charge×potential difference
A special power supply is needed to provide the high potential difference of 6200 V6200\text{ V}6200 V.
Describe one safety risk associated with using this power supply.
The figure below shows the emission spectrum for each of three different galaxies and a laboratory reference source on Earth.
The emission spectrum for each galaxy shows red-shift. Explain what is meant by the term red-shift.
Which galaxy in the figure is furthest from the Earth? Give a reason for your answer.
State which theory the spectra from each galaxy gives evidence for.