Which of the following statements are correct about a planet rotating around the sun in an elleptical orbit

Options

A. its areal velocity is constant
B. its angular momentum is constant
C. its mechanical energy is constant
D. its time period of proprtional to `r^(3)`

Answer

A, B, C

Explanation

When a planet is rotating around the sun in an elliptical orbit, then areal velocity, angular momentum and mechanical energy are constant but `T^(2) prop r^(3)` and not `t prop r^(3)`.