Q. A comet moves around the sun in an elliptical orbit. It is closest to the sun at a distance $d_{1}$ and its corresponding velocity is $v_{1}$, and if it is farthest from the sun at a distance $d_{2}$, then the corresponding velocity is :

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A

$\frac{v_{1}}{d_{1}} \cdot d_{2}$

10%

B

$v_{1} \cdot \frac{d_{1}}{d_{2}}$

18%

C

$v_{1} \cdot \sqrt{\frac{d_{2}}{d_{1}}}$

38%

D

$v_{1} \cdot \sqrt{\frac{d_{1}}{d_{2}}}$

33%

Solution:

Angular momentum of the comet is conserved.

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