Which method did Ole Rømer use to show that light did not travel at infinite speed?

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1 Homework 8! This is a preview of the draft version of the quiz Started: Mar 25 at 8:26am Quiz Instruc!ons Question 1 Ultraviolet light differs from orange light in that it always travels more quickly than orange light always has a longer wavelength than orange light always travels more slowly than orange light always has a shorter wavelength than orange light Question 2 Which method did Ole Rømer use to show that light did not travel at infinite speed? Rømer sent light through a rotating opaque disk with holes in it, bounced it off a mirror and found it did not return through the same hole Rømer measured a delay between the instant that he sent a flash of light to a mirror on a distant hill and the return of the reflected flash Rømer observed that eclipses of Jupiter's moons by the planet appeared to occur later when the Earth was farther away from Jupiter Rømer bounced a beam of light off the Moon and measured a delay between when the light was sent and the time it returned from the Moon

2 Question 3 Two physicists in different countries discover that they have made ideal black bodies from very different materials. Without conducting tests, they know that the peak wavelength of the continuous spectrum of radiation emitted by these two objects will be different if the amount of light used to illuminate the black bodies is different identical if the black bodies have the same size, but not otherwise different because the black bodies were made from different materials identical if the black bodies are at the same temperature, but not otherwise Question 4 Orange light has a wavelength of 600nm. The H-alpha spectral line of hydrogen has a longer wavelength of nm. In which wavelength range does the Lyman- Alpha line appear? Red light Green light Ultraviolet Blue light Question 5 A cloud of hot hydrogen gas will display what type of spectrum?

3 A mix of emission and absorption lines in a pattern of wavelengths that corresponds to hydrogen A black body spectrum with absorption lines in a pattern of wavelengths that corresponds to hydrogen A series of emission lines in a pattern of wavelengths that corresponds to hydrogen A uniform black body spectrum containing all of the colors of visible light Question 6 The average temperature of Venus is more than that of the Earth. What would be the relative wavelengths of the peak emissions of the continuous, black body spectra from these planets? The emission from the two planets would peak at the same wavelength, but at different energies The wavelength of peak emission from the Earth would be at a longer wavelength than that from Venus The wavelength of peak emission from Venus would be at a longer wavelength than that from the Earth It is not possible to predict the outcome of this experiment from the information given Question 7 Consider an atom in which electrons occupy three energy levels of highest, middle, and lowest energy. The atom is illuminated by photons of light with many different wavelengths from a black body. This causes the atom to absorb some photons and to re-emit them at a slightly later time. The emission line with the shortest wavelength could be produced by the electron transition from

4 (Hint: the lowest energy level, which is also called the ground state, is the one closest in energy to the center of an atom) lowest to middle lowest to highest highest to lowest middle to lowest Question 8 Star A displays a parallax of 1/6 of an arcsecond. Star B has an absolute magnitude of +2.3 and an apparent magnitude of Star C has an absolute magnitude of +1.7 and an apparent magnitude of What is the relative distance of these stars from the Earth? Star C is farthest away, star B is closest Star C is farthest away, star A is closest Star B is farthest away, star A is closest Star A is farthest away, star B is closest Question 9 The stars α Andromedae (α And), β Andromedae (β And), σ Sagittarii (σ Sgr) and θ Centauri (θ Cen), all have an apparent magnitude of about Their absolute magnitudes are about α And = -0.2, β And = -1.9, σ Sgr = -2.1, θ Cen = Which of these stars is the most luminous (intrinsically the brightest) and which is closest to the Earth? σ Sgr is the most luminous; θ Cen is the closest to the Earth

5 σ Sgr is the most luminous; σ Sgr is the closest to the Earth θ Cen is the most luminous; θ Cen is the closest to the Earth θ Cen is the most luminous; σ Sgr is the closest to the Earth Question 10 The nearest star to the Earth, Proxima Centauri, is at a distance of 4.24 lightyears. Kapteyn's Star is a class M red subdwarf at a distance of light years, about three times as far away as Proxima Centauri. Kapteyn's Star displays a parallax about one-ninth of the parallax displayed by Proxima Centauri one-third of the parallax displayed by Proxima Centauri nine times the parallax displayed by Proxima Centauri three times the parallax displayed by Proxima Centauri Not saved Submit Quiz