Question

A planet moves around the sun. At a point P, it is closest from the sun at a distance d1, & has a speed v1. At another point Q, when it is farthest from the sun at a distance d2, its speed will be...?

Answer 1

A planet moves around the sun. At a point P, it is closest from the sun at a distance d1, & has a speed v1. At another point Q, when it is farthest from the sun at a distance d2, its speed will be d1²v1/ d2²

Answer 2

Explanation:

from conservation of angular momentum at these two points

d1v1=d2v2

.

. . v2 =d1v1/d2