Kepler’s law

Question 1:  How did Newton extend his notion of Gravity to Explain Planetary Motion?

Answer:

Newton’s First law is an inverse square law, i.e. it says that the force between two objects is inversely proportional to the square of their distances whereas, Kepler’s 1st Law states that the planets revolve around the sun in elliptical orbits with Sun at one focus. The two law support each other in defining the motion of the planets.

Question 2: How Kepler’s First Law describes the Shape of an Orbit?

Answer:

Kepler’s First Law also called Law of orbits, states that planets revolve around the sunfollowing an elliptical path and sun is at any of the focus of the ellipse.

Question 3: How Kepler’s Second Law describes the way a planet’s speed varies along its orbit?

Answer:

According to Kepler’s Second Law of Planetry motion, the areal speed of a planet is always constant. So it the planet is closer to sun it accelerates at faster velocity and if the planet is away from sun it accelerates slowly.

Question 4: How does Kepler’s Third Law compare the motion of planets in orbits of different sizes?

Answer:

According to Kepler’s Third Law of Planetry motion, The square of time taken by the planets to complete the one rotation is directly proportional to the cube of semi major axis of the elliptical orbit of the planet.

Question 5: Why are the orbits of the planets not circular?

Answer:

Circular orbits demands that the orbit of planets should be certain but in cosmos the velocity of planets are not certain always and a slight change in velocity results in elliptical orbits of planets.

Kepler’s law of planetary motion is the basic law that is used to define the motion of planets around the stars. These laws work in parallel with Newton’s Law and Gravitation Law and are helpful in studying the motion of various planetary objects.

Kepeler’s law provides three basic laws which are,

• Kepler’s First law (Law of Orbits)
• Kepler’s Second law (Law of Areas)
• Kepler’s Third law (Law of Periods)

These laws are provided by the German astronomer Johannes Kepler, hence the name Kepeler’s Law. Let’s learn about these in detail in this article.