Concept explainers
(a)
The wavelength of the sodium line emitted from galaxies.
(a)
Answer to Problem 41P
The wavelength of the sodium line emitted from galaxies is
Explanation of Solution
Write the expression for velocity from Hubble’s law.
Here,
Write the expression for the wavelength by using equation (I).
Here,
Conclusion:
Substitute,
Thus, the wavelength of the sodium line emitted from galaxies is
(b)
The wavelength of the sodium line emitted from galaxies.
(b)
Answer to Problem 41P
The wavelength of the sodium line emitted from galaxies is
Explanation of Solution
Write the expression for velocity from Hubble’s law.
Here,
Write the expression for the wavelength by using equation (I).
Here,
Conclusion:
Substitute,
Thus, the wavelength of the sodium line emitted from galaxies is
(c)
The wavelength of the sodium line emitted from galaxies.
(c)
Answer to Problem 41P
The wavelength of the sodium line emitted from galaxies is
Explanation of Solution
Write the expression for velocity from Hubble’s law.
Here,
Write the expression for the wavelength by using equation (I).
Here,
Conclusion:
Substitute,
Thus, the wavelength of the sodium line emitted from galaxies is
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Chapter 31 Solutions
Principles of Physics: A Calculus-Based Text
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- The geometry of spacetime in the Universe on large scales is determined by the mean energy density of the matter in the Universe, ρ. The critical density of the Universe is denoted by ρ0 and can be used to define the parameter Ω0 = ρ/ρ0. Describe the geometry of space when: (i) Ω0 < 1; (ii) Ω0 = 1; (iii) Ω0 > 1. Explain how measurements of the angular sizes of the hot- and cold-spots in the CMB projected on the sky can inform us about the geometry of spacetime in our Universe. What do measurements of these angular sizes by the WMAP and PLANCK satellites tell us about the value of Ω0?arrow_forwardNear the center of our galaxy, hydrogen gas is moving directly away from us in its orbit about a black hole. We receive electromagnetic radiation of wavelength 1888 nm and know that it was 1875 nm when emitted by the hydrogen gas. Randomized Variablesλ = 1888 nm What is the ratio of the speed of the gas to the speed of light?arrow_forwardAn electron in a hydrogen atom has a speed about the proton of 2.2x10° m/s. the relativistic and Newtonian values of kinetic energy will be differ by... 0.0055 % O 0.0078% O 0.0034% O 0.0087%arrow_forward
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