Suppose you discovered a galaxy with a mass-to-light ratio of 0.1 solar mass per solar luminosity. What would this measurement say about the nature of the stars in this galaxy?
What will be an ideal response?
If a galaxy has a lower mass-to-light ratio than 1, then the ratio of massive hot stars to dim cool stars in this galaxy must be higher than that ratio in our own galaxy (or indeed every other galaxy observed to date). If I had confidence in my observations, I might suspect that the star formation in this galaxy must have produced an unusual predominance of high-mass stars.
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Jet streams not only play an essential role in the global transfer of thermal energy but also aid
A) eastbound airplanes. B) westbound airplanes. C) both eastbound and westbound airplanes. D) landings and takeoffs.
Calculate the peak heat flux for nucleate pool boiling of water at 300 kPa pressure and 110°C on clean copper.
GIVEN
? Nucleate pool boiling of water on clean copper
? Pressure = 3 atm
? Water temperature (Tw) = 390°C
Find
? The peak heat flux (q"max)
ASSUMPTIONS
? Steady state
PROPERTIES AND CONSTANTS
From Table 9.2, the surface tension at 133°C (o) = 0.0522 N/m
A source emits sound at a fixed constant frequency f.If the source moves away from you, and at the same time you run away from the source, the frequency you hear is
a. the same as f. b. higher than f. c. lower than f. d. unrelated to f.
Lunar ________ are the result of ancient lava flows on the Moon
Fill in the blank(s) with correct word