Answer:
4.7 years
Step-by-step explanation:
Distance of planet from Earth = 1.3 parsec
We know that 1 parsec = 3.26 light years
And a light year is the distance traveled by light in time period of 1 year.
So, Distance of planet from Earth = 1.3 [tex]\times[/tex] 3.26 = 4.24 light years
Given that, the person travels at a speed equal to 90% of the light speed.
To travel to the planet from Earth, Light takes 4.24 years.
To travel the distance [tex]D[/tex], at a speed [tex]s[/tex] light takes time of 4.24 years.
To travel the distance [tex]D[/tex], at a speed [tex]0.90s[/tex], the person takes time:
[tex]\dfrac{4.24}{0.90} = \bold{4.7\ years}[/tex]
So, the twin on Earth ages by 4.7 years.
