Hubble's Law is important because ....
A. it showed the existence of dark matter in all galaxies.
B. it showed the universe is expanding.
C. it can be used to estimate the age of Irregular galaxies.
D. it explained the rotational velocity curves of spiral galaxies.
Answer: B. it showed the universe is expanding.
You might also like to view...
Why does the image show very few stars?
A: It is hard to find stars in the Milky Way Galaxy, so it would have been too difficult to select a region that had many. B: Stars are only visible in radio waves, and the Hubble Deep Field image was taken in the optical region of the spectrum. C: Stars are only visible in the optical region of the spectrum, and the Hubble Deep Field image was taken with a radio telescope. D: It was chosen so that bright stars in the Milky Way Galaxy do not interfere with our picture of the distant universe. E: The scientists were interested seeing the light of galaxies through a region of space filled with black holes.
Calculate the energy En (in eV) of a hydrogen atom's electron with n = 4
a. –54 eV b. –3.4 eV c. –0.85 eV d. –1.7 eV
A long wire carrying a 2.0-A current is placed along the y-axis. What is the magnitude of the magnetic field at a point that is 0.60 m from the origin along the x-axis? (?0 = 4? × 10-7 T ? m/A)
A) 6.7 T B) 0.67 µT C) 0.12 µT D) 1.3 µT E) 12 T
A wavelength of 540 nm yields a first-order maximum at 13.4° with a grating. At what angle will the second-order maximum appear for this wavelength?
a. No second-order maximum exists in this case. b. 90° c. –13° d. 28° e. 1.16°