Question

explain question no 5

Answer 1

By Kepler's law

T2αa3T2αa3

T21a31=T22a32T12a13=T22a23

T22=(a2a1)3T22=(a2a1)3×T21×T12

T22=(12)3T22=(12)3×T21×T12

T22=(18)T22=(18)×1year×1year

T2=18–√T2=18×365days×365days

=129days

$hope \: that \: this \: answer \: will \: help \: u$