While examining the spectrum of a galaxy you find all the hydrogen lines are shifted to longer wavelengths. This galaxy is
A) moving away from us.
B) moving towards us.
C) expanding explosively.
D) blue shifted.
E) not forming new stars.
A
You might also like to view...
Vegetable oil is boiled by passing steam at 215ºF through a 1-inch ID by 1.25-inch OD steel tube. Predict the overall heat transfer coefficient based on the outside area of the tube if the convective heat transfer coefficients are 25 Btu/hr?ft^2?ºF for steam and 15 Btu/hr?ft^2 ?ºF for the vegetable oil. Neglect fouling factors.
What will be an ideal response?
Force on a Moving Charge: A negatively-charged particle moves across a constant uniform magnetic field that is perpendicular to the velocity of the particle. The magnetic force on this particle
A. causes the particle to speed up. B. causes the particle to slow down. C. causes the particle to accelerate. D. is in the same direction as the particle's velocity. E. is opposite the direction of the particle's velocity.
All the following statements about Mars are true. Which one might have led to a significant loss of atmospheric gas to space?
A) Mars lost any global magnetic field that it may once have had. B) The axis tilt of Mars is thought to change significantly with time. C) Outgassed water molecules are split apart, and the oxygen then reacts chemically with surface rock on Mars. D) Mars probably once had a much higher density of greenhouse gases in its atmosphere than it does today.
Absolute zero is the temperature
A. of the freezing point of water. B. on the coldest day recorded at Nome, Alaska. C. at which an ideal gas would exert zero pressure. D. of the freezing point of mercury. E. of the boiling point of liquid helium.