In planetary motion, the quantity that remains unchanged is

Question

In planetary motion, the quantity that remains unchanged is (A) radius of the orbit (B) speed along the orbit (C) total angular momentum (D) angular speed

Tardigrade Admin · Accepted Answer

The line joining the sun to the planet sweeps out equal areas in equal interval of time ie, areal velocity is constant. According to law of area planet will move slowly when it is farthest from sun and more rapidly when it is nearest to sun. It is similar to law of conservation of angular momentum.

Q. In planetary motion, the quantity that remains unchanged is

radius of the orbit

speed along the orbit

total angular momentum

angular speed

The line joining the sun to the planet sweeps out equal areas in equal interval of time ie, areal velocity is constant. According to law of area planet will move slowly when it is farthest from sun and more rapidly when it is nearest to sun. It is similar to law of conservation of angular momentum.