Question

Hubble's law is expressed as (here, $v=$ speed of recession, $r=$ distance of galaxy, $H=$ Hubble constant).

• A. $v=Hr$
• B. $v=H^{2}r$
• C. $v=\frac{H}{r^2}$
• D. $v=H{r}^2$

Answer 1

Answer: (A)

$v=Hr$

According to Hubble's law, speed of recession is directly proportional to the distance of galaxy i.e. $v\propto r$
$\Rightarrow v=Hr$
where, H is Hubble's constant.