Question

Alpha century is 4 light years from earth how long would it take for light form alpha centauri to reach earth

Answer 1

4 Earth years. I hope this helps

Answer 2

Given:

Distance of alpha century = 4 light year

Speed of light = 3 ×
`10^(8)` m

To find:

Time taken by light to reach earth = ?

Formula used:

Distance = speed × time

Solution:

Distance = 4 light year

Converting distance from light year into meter

1 light year = 365 × 24 × 60 × 60

4 light year = 4 × 365 × 24 × 60 × 60× 3 ×
`10^(8)`

As we know,

Distance = speed × time

s = v × t

Where s = distance

v = velocity

t = time

So,t =
`(s)/(v)`

t =
}{3 ×
`10^(8)}`

t = 4 × 365 × 24 × 60 × 60 second

t = 4 year

Thus, Time taken by light to reach earth from alpha century is 4 earth year.