Planet 1 and planet 2 are both in circular orbits around the same central star.The orbit of planet 2 has a radius that is much larger than the radius of the orbit of planet 1.This means that:
A)the period of planet 1 is greater than the period of planet 2 and the speed of planet 1 is greater than the speed of planet 2
B)the period of planet 1 is greater than the period of planet 2 and the speed of planet 1 is less than the speed of planet 2
C)the period of planet 1 is less than the period of planet 2 and the speed of planet 1 is less than the speed of planet 2
D)the period of planet 1 is less than the period of planet 2 and the speed of planet 1 is greater than the speed of planet 2
E)the planets have the same speed and the same period

Question

Quizplus · Accepted Answer

According to Kepler's third law of planetary motion, the square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit. This means that a planet with a larger orbital radius (like planet 2) will have a longer period than a planet with a smaller orbital radius (like planet 1). Additionally, in circular orbits, the orbital speed is inversely proportional to the square root of the orbital radius, meaning that planet 1, with its smaller orbit, moves faster than planet 2.

Planet 1 and Planet 2 Are Both in Circular Orbits