(D) PART CORRECT OPTION.
Dark matter is believed to be present at the galactic center. The galaxies revolve around this unobservable matter called dark matter.
Jestion 6 Stars farther out in the disks of spiral galaxies seem to orbit the galaxy...
Galaxies contain both stars and dark matter. The mass M of a galaxy that is located within a certain star's orbit is given by where v is the velocity of the star, r is the distance from the galaxy's center to the star, and G is Newton's gravitational constant, 6.673 x 10- N m/kg Stars near the edge of a particular galaxy have velocities of 259 km/s. The radius of the galaxy is 53 kpc. How much mass is in...
1/ Sirius A has a luminosity of 9.98 x 10^27 W and a surface temperature of about 9400K. What is its radius? A/ r = 7.56 x 10^8 m B/ r = 1.34 x 10^9 m C/ r= 1.26 x 10^13 m D/ r = 7.94 x 10^-14 m 3/ which of the following stellar properties is the most fundamental to a star’s main-sequence and post-main sequence life? A/ temperature B/ mass C/ luminosity D/ radius 4/ Stars Moppit and...