KCET 2025 Physics Paper

Angular momentum is conserved in an elliptical orbit, meaning:$L_p = L_a$where $L_p$ is the angular momentum at perihelion and $L_a$ is the angular momentum at aphelion.The perihelion is the point in the orbit where the planet is closest to the Sun. Therefore, the radius at perihelion $(r_p)$ is less than the radius at aphelion $(r_a)$ :$r_p < r_a$ Because angular momentum is conserved, we have:$m v_p r_p = m v_a r_a$From this, it follows that the velocity at perihelion $(v_p)$ is greater than the velocity at aphelion $(v_a)$ :$v_p > v_a$