Which of the following features of a telescope determines its light gathering power?
a. The focal length of the objective
b. The focal length of the eyepiece
c. The diameter of the objective
d. Length of the telescope tube
e. None of the above.
C
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Potassium-40 decays to argon-40 has a half-life of 1.25 billion years. Suppose you find a rock that has only 1/8 of its original potassium-40 still remaining. How old is the rock?
A) 3.75 billion years B) 5.25 billion years C) 2.5 billion years D) 1.25 billion years E) 4.5 billion years
The work done on an ideal gas system in an isothermal process is -400 J. What is the change in internal (thermal) energy of the gas?
A) 0 J B) -400 J C) 400 J D) 200 J
As you move farther away from a source emitting a pure tone, the __________ of the sound you hear decreases
Fill in the blank(s) with correct word
As air rises, it expands. It expands because it moves to
A) a region of higher air pressure. B) a region of lower air pressure. C) an area of greater humidity. D) an area of cooler air temperature.