Given below are two statements: Assertion (A): The radius vector from the Sun to a planet sweeps out equal areas in equal intervals of time and thus areal velocity of planet is constant. Reason (R): For a central force field the angular momentum is a constant.
❓ Question Given below are two statements: one is labelled as Assertion (A) and the other as Reason (R): Assertion (A): The radius vector from the Sun to a planet sweeps out equal areas in equal intervals of time and thus the areal velocity of the planet is constant. Reason (R): For a central force field, the angular momentum is a constant. 🖼️ Question Image ✍️ Short Solution To check whether the Assertion and Reason are correct, and whether R explains A , let’s analyze both step by step. 🔹 Assertion (A) Explanation The statement says that the radius vector from the Sun to a planet sweeps out equal areas in equal intervals of time. This is Kepler’s Second Law of Planetary Motion , also known as the Law of Equal Areas . Mathematically, the areal velocity (dA/dt) is given by: d A d t = 1 2 r 2 d θ d t If dA/dt = constant , then the area swept per unit time remains the same — meaning areal velocity is constant. ✅ So, Assertion (A) is true. 🔹 ...