Question

Light travels at 3 x 105 km/s (300,000 km or 186,000 miles). How long will it take to get to earth? (A distance of 1.5 x 108 km)

0.2 s

0.8 s

8 s

8 minutes

Answer 1

Option (4)

Step-by-step explanation:

Here, Speed of light=
`3*10^5` Km/sec

Distance=
`1.5*10^8` Km

We know that,

`Speed=(Distance)/(Time)`

`\implies Time=(Distance)/(Speed)`

`Time=(1.5*10^8)/(3* 10^5)`

`=0.5 *10^3`

=500 sec

=8 minutes 20 sec

Hence, the correct answer is option (4) i.e 8 minutes.