Question

The ratio of mean distances of three planets from the sun are 0.5,1, 1.5, then the square of time periods are in the ratio of:

• A. $1:4:9$
• B. $1:9:4$
• C. $1:8:27$
• D. $2:1:3$

Answer 1

The correct option is C $1:8:27$

$T^2<r^3$

$r_1:r_2:r_3=\frac{1}{2}:1:\frac{3}{2}$

$T_1^2:T_2^2:T_3^2=\frac{1}{8}=1:\frac{27}{8}=1:8:27$