Question

Astronomers believe that the universe is expanding, and stellar objects are moving away from us at a radial velocity v proportional to the distance from Earth to the object.

(a) Write V as a function of D using H as the constant of proportionality:
a) V = HD
b) V = H/D
c) V = H * D
d) V = D/H

Answer 1

The correct function expressing the radial velocity V as a function of the distance D with H as the proportionality constant is V = H × D, describing the direct proportionality according to Hubble's Law.

Step-by-step explanation:

According to Hubble's Law, the radial velocity V of stellar objects moving away from us is directly proportional to their distance D from Earth. Therefore, the correct way to express V as a function of D using H as the constant of proportionality is V = H × D, where H is the Hubble constant. The other options presented do not correctly represent this direct proportionality between velocity and distance as established by Hubble's observations of the expanding universe.