Briefly explain how we can use spectral lines to determine an object's radial motion (toward or away from us). Can we also learn the object's tangential motion (across our line of sight) from its spectral lines?
What will be an ideal response?
By comparing the wavelength of the spectral lines in the object's spectrum to the rest wavelengths of the same lines, we measure the Doppler shift. This tells us the object's radial motion: A shift toward shorter wavelength means the object is moving toward us, and a shift to longer wavelength means it is moving away from us. We cannot learn anything about the object's tangential motion from its spectral lines because this does not affect the line positions.
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Emperor penguins are part of the species forsteri and genus aptenodytes. Given this, their scientific classification would be written
A) Aptenodytes Forsteri B) forsteri Aptenodytes C) Forsteri aptenodytes D) Aptenodytes forsteri
Exhibit 12-1
The figure below shows a graph of angular velocity versus time for a woman bicycling around a circular track.
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Use this exhibit to answer the following question(s).
Refer to Exhibit 12-1. What is her angular displacement (in rad) in the first 12 minutes?
A. 0 B. 2? C. 4? D. 16? E. 32?
Two experimental runs are performed to determine the calorimetric properties of an alcohol which has a melting point of -10° C
In the first run, a 200-g cube of frozen alcohol, at the melting point, is added to 300 g of water at 20°C in a styrofoam container. When thermal equilibrium is reached, the alcohol-water solution is at a temperature of 5°C. In the second run, an identical cube of alcohol is added to 500 g of water at 20°C and the temperature at thermal equilibrium is 10°C. The specific heat capacity of water is 4190 J/kg ? K. Assume no heat is exchanged with the styrofoam container and the surroundings. What is the specific heat capacity of the alcohol? A) 1700 J/kg ? K B) 1900 J/kg ? K C) 2100 J/kg ? K D) 2300 J/kg ? K E) 2500 J/kg ? K
This photo shows the Large Magellanic Cloud, or LMC for short. Based on what you have learned in about the LMC from your text, which of the following statements about the LMC is not true?
A) Galaxies similar to the LMC are extremely rare. B) It is an irregular galaxy. C) It orbits the Milky Way Galaxy. D) Its color indicates active star formation.