OnlineCBT
Physics · GRAVITATION
हिन्दीConsider the following statements regarding planetary motion around the Sun: (A) The orbit of a planet is an ellipse with the Sun situated at one of the foci. (B) The areal velocity \( \frac{\Delta A}{\Delta t} \) of a planet is directly proportional to its mass \( m \). (C) The square of the orbital period is proportional to the cube of the semi-major axis. (D) The linear speed of a planet remains constant at all points on its elliptical orbit. Which of the above statements are correct?
Correct answer · Option 2
(A) and (C) only
Explanation
Statements (A) and (C) are Kepler's 1st and 3rd laws. (B) is false because dA/dt = L/(2m) = (1/2) r v_perp, which is independent of mass for a given orbit. (D) is false as speed varies between perihelion and aphelion.
