Question

If the distance of the earth from Sun is $15 \times 10^6 km$ Then the distance of an imaginary planet from Sun, if its period of revolution is $2.83$ years is :

• A. $6 \times 10^6 km$
• B. $3 \times 10^6 km$
• C. $6 \times 10^7 km$
• D. $3 \times 10^7 km$

Answer 1

Answer: (B)

$3 \times 10^6 km$

Answer 2

The correct answer is (B) : $3 \times 10^6 km$
T2∝R3⇒(T2​T1​​)2=(R2​R1​​)3
⇒(2.831​)2=(R2​1.5×106​)3
⇒R2​=[(2.83)2×(1.5×106)3]1/3
=81/3×1.5×106=3×106km