If the universe is closed and finite, then
a. the universe will expand forever
b. the universe has a center
c. the universe has an edge
d. none of the above
D
You might also like to view...
If in a double-slit experiment the slit separation is increased, which of the following happens to the interference pattern shown on the screen?
A) The minima get closer together. B) The maxima stay at the same position. C) The minima and maxima stay at the same position. D) The minima stay at the same position. E) The maxima get further apart.
Which of the following is the most basic definition of a greenhouse gas?
A) a gas that reflects a lot of sunlight B) a gas that keeps warms air from rising, and therefore warms the surface C) a gas that absorbs infrared light D) a gas that makes a planet much hotter than it would be otherwise, even in small amounts
During the volcanic eruption of Mt. Pelee in 1902, an incredibly hot "burning cloud" rolled down the mountain and incinerated the town of Saint-Pierre. From the damage done, the temperature in the cloud was estimated at 700°C. If the air temperature
was 20°C and a mole of air is 29 grams, estimate the molecular weight of the gas in the "burning cloud" that made it heavier than the surrounding air. (As a follow-on, estimate the most probable composition of the cloud. Some typical volcanic gases are H2S, SO2, H2SO4, CO2, NO.)
Imagine that the energy levels of a certain system are proportional to 
, where n = 1, 2, 3, …. Imagine that for some reason, only transitions such that ?n = 1 are physically possible. In a spectrum chart (like the one shown in figure Q11.2) the emission lines produced by this system
A. Get closer together (in energy) as we go to the right.
B. Are evenly spaced (in energy).
C. Get farther apart (in energy) as we go to the right.