Question

The earth revolves round the sun in one year. If the distance between them become doubles, then the new period of the revolution will be :

• A. 1/2 yr
• B. $2\sqrt{2}$
• C. 4 yr
• D. 8 yr

Answer 1

The correct option is B $2\sqrt{2}$

According to Keplar's law

$T^2\infty R^3$

${\left(\frac{T_1}{T_2}\right)}^2={\left(\frac{R_1}{R_2}\right)}^3$

${\left(\frac{1}{T_2}\right)}^2={\left(\frac{R}{2R}\right)}^3$

$\frac{1}{T_2}=\frac{1}{8}$

$T_2=2\sqrt{2}yr$