From laboratory measurements, we know that a particular spectral line formed by hydrogen appears at a wavelength of 121.6 nanometers (nm). The spectrum of a particular star shows the same hydrogen line appearing at a wavelength of 121.8 nm
What can we conclude? A) The star is moving toward us.
B) The star is moving away from us.
C) The star is getting hotter.
D) The star is getting colder.
E) The "star" actually is a planet.
B
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Determine the maximum heating rate to the inner surface of the casting due to the release of heat of fusion in the molten iron.
Answer the following statement(s) true (T) or false (F)
1. 
2. 
3. 
A radio transmitter broadcasts at a frequency of 200,000 Hz. What is the wavelength of the wave?
The electric potential inside a charged solid spherical conductor in equilibrium
a. is always zero. b. is constant and equal to its value at the surface. c. decreases from its value at the surface to a value of zero at the center. d. increases from its value at the surface to a value at the center that is a multiple of the potential at the surface. e. is equal to the charge passing through the surface per unit time divided by the resistance.