Question

Inian and Ezhilan argue about the light year. Iniyan tells that it is 9.46×10^15m and Ezhilan argues that it is 9.46×10^12 m.Who is right, justify your answer

Answer 1

Given : Inian and Ezhilan argue about the light year. Iniyan tells that it is 9.46×10^15m and Ezhilan argues that it is 9.46×10^12 m.

To check : who is right and also justify your answer.

solution : A light year is the distance travelled by light in a year.

we know, speed of light = 3 × 10^8 m/s

one year = 365 × 24 × 3600 seconds.

as distance = speed × time

= 3 × 10^8 × 365 × 24 × 3600

= 3 × 365 × 24 × 3600 × 10^8 m

= 946,080 × 10^10 m

= 9.4608 × 10^15 m ≈ 9.46 × 10^15 m

hence, a light year = 9.46 × 10^15 m

so it is clear that Iniyan is right. why is she right ?, answer of this question is mentioned in above explanation.