Which of the following is TRUE?

a) It is possible for galaxies that are very distant to actually move through space ata speed several times the speed of light.
b) A redshift occurs when a photon loses energy and slows down as itmoves through space.
c) We see distant galaxies as they were billions or even tens of billions ofyears ago.
d) We measure a redshift for roughly half of the galaxies that we observe, and for theothers we measure a blueshift.
e) The center of the universe is located at a point about 200 Mpc from us in the centerof a cluster of galaxies.


Answer: c) We see distant galaxies as they were billions or even tens of billions ofyears ago.

Physics & Space Science

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A. points in the +x direction. B. points in the ?x direction. C. points in the +y direction. D. points in the ?y direction. E. points in the +z direction. F. points in the ?z direction. T. is zero.

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A 2.0-m wire carries a current of 15 A directed along the positive x axis in a region where the magnetic field is uniform and given by B =  mT. What is the resulting magnetic force on the wire?

A.

(+1.2 ) N

B.
(?1.2 ) N

C.
(?1.5 ) N

D.
(+1.5 ) N

E.
(+0.90 ) N

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Compared to the amount of electric current in the filament of a lamp, the amount of current in the connecting wire is

A) definitely less. B) often less. C) actually more. D) the same. E) incredibly, all of the above

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