Q.

If the distance of the Earth from the Sun is 1.5×106 km, then the distance of an imaginary planet from the Sun, if its period of revolution is 2.83 years is:      [2023]

1 6×106 km  
2 3×106 km  
3 6×107 km  
4 3×107 km  

Ans.

(2)

T2R3(T1T2)2=(R1R2)3

(12.83)2=(1.5×106R2)3

R2=[(2.83)2×(1.5×106)3]1/3

            =81/3×1.5×106=3×106 km