Question

According to Hubble’s law, what is the recessional velocity of a galaxy that is 108 light-years away from us? (Assume a Hubble constant of 22 km/s per million light-years.)

Answer 1

the recessional velocity of the galaxy is 2.736×10^-3 km/s

Step-by-step explanation:

for the recessinal velocity of the galaxy as v and d being the distance of the galaxy from us and H as the hubble constant, then hubbles law says:

v = H×d

= (22 km/s per million light years)×108 light years

= (2.2×10^-5 km/s per light years)×108 light years

= 2.376×10^-3 km/s

Therefore, the recessional velocity of the galaxy is 2.736×10^-3 km/s