KE = 1/2(100 kg)(100 m/s)^2 = 500000 Joules ----------------------- KE = 1/2(100 kg)(50 m/s)^2 = 125000 Joules ---------------------- 5â¦00000 Joules/125000 Joules = 4 ------ The kinetic energy is reduced by a factor of 4 because the speed is squared.
Earth, the fifth-largest of the eight planets in the Solar System belongs to the Milky Way galaxy and is orbiting about 28,000 light years from the center of the galaxy. It is believed that currently it lies about 20 light years above the galaxy's equatorial plane in the Orion spiral arm.
A galaxy is a group of many stars, along with gas, dust, and dark matter. The name 'galaxy' is taken from the Greek word galaxia meaning milky, a reference to our own galaxy, the Milky Way. Gravity holds galaxies together against the general expansion of the universe. In effect, the expansion of the universe takes place between groups of galaxies, not inside those groups.