If a spherical galaxy of diameter 100,000 ly contained enough mass to be a black hole, what would be its mass?
A)
200 x 109 kg
B)
400 x 109 kg
C)
6.9 x 1023 kg
D)
3.2 x 1047 kg
E)
6.4 x 1047 kg
D
You might also like to view...
The graph shows how a star's orbital speed varies with time because of the gravitational tug of an orbiting planet. These data were obtained by measuring
A) the precise wavelengths of spectral lines in the spectrum of the star. B) the precise wavelengths of spectral lines in the spectrum of the orbiting planet. C) the precise brightness of the star divided by the precise brightness of the planet. D) the orbital period of the planet that is orbiting the star.
You have a parallel circuit in a house that operates on 120 V with several outlets for plugging in appliances and it has a 20 A fuse in the circuit. What is the maximum number of 600-W appliances that can be plugged into the outlets without "blowing" the fuse? Assume that if the current flow exceeds the rating of the fuse, it will blow
a. 2 b. 4 c. 5 d. 7
The size of the current flowing through a conductor equals the __________ divided by the conductor's ___________
Fill in the blank(s) with correct word
Two beams of coherent light travel different paths arriving at point P. If the maximum constructive interference is to occur at point P, what should be the phase difference between the two waves?
A) The phase difference between the two waves is ?/4. B) The phase difference between the two waves is ?/2. C) The phase difference between the two waves is ?. D) The phase difference between the two waves is 2?. E) The phase difference between the two waves is 5?/2.