What does it mean that a planet sweeps equal areas in equal time?

Asked By: Jene Wallerand | Last Updated: 6th February, 2020
Category: science physics
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An imaginary line joining a planet and the sun sweeps out an equal area of space in equal amounts of time. The dot pattern shows that as the planet is closest the sun, the planet is moving fastest and as the planet is farthest from the sun, it is moving slowest.

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Similarly, you may ask, why do you think the area swept out by a planet in a given period of time remains constant?

The area the planet sweeps over is equal because when it speeds up the length covered along the orbital path is greater, but it is also closer to the star, and that dimension is decreased.

Furthermore, what does Kepler's law of equal area describe? Kepler's second law of planetary motion describes the speed of a planet traveling in an elliptical orbit around the sun. It states that a line between the sun and the planet sweeps equal areas in equal times. Thus, the speed of the planet increases as it nears the sun and decreases as it recedes from the sun.

Then, what is meant by Kepler's second law which states that as a planet moves around its orbit it sweeps out equal areas in equal times?

Kepler's second law states that a planet moves in its ellipse so that the line between it and the Sun placed at a focus sweeps out equal areas in equal times.

What is Kepler's 1st law?

Kepler's first law - sometimes referred to as the law of ellipses - explains that planets are orbiting the sun in a path described as an ellipse. The resulting shape will be an ellipse. An ellipse is a special curve in which the sum of the distances from every point on the curve to two other points is a constant.

31 Related Question Answers Found

What shape is the orbit use the screenshot to explain this?

___________________________________________________________________________________________________________________________3Author: Simon Lees 2017Screenshot of the trajectoryScreenshot of the trajectoryScreenshot of the directionGravity holds the planet in orbit. The shape is circular or oval shape.

What are the 3 laws of Kepler?

There are actually three, Kepler's laws that is, of planetary motion: 1) every planet's orbit is an ellipse with the Sun at a focus; 2) a line joining the Sun and a planet sweeps out equal areas in equal times; and 3) the square of a planet's orbital period is proportional to the cube of the semi-major axis of its

What is Kepler's third law simplified?

“The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit” That's Kepler's third law. In other words, if you square the 'year' of each planet, and divide it by the cube of its distance to the Sun, you get the same number, for all planets.

What is G in Kepler's third law?

The Newtonian constant, G, is defined in terms of the force between two two masses separated by some fixed distance. In order to measure k, all you need to do is count days; in order to measure G, you need to know very precisely the masses, separation, and forces between test objects in a laboratory.

What is the law of equal areas?


The law of equal areas states that as a planet orbits the Sun the area it sweeps out is always equal over an equal amount of time no matter where it is in its orbital path. Since orbits are elliptical, this means as a planet gets closer to the Sun its velocity must increase for this law to remain true.

Why is Kepler's first law important?

Kepler's first law states that the planets travel around the sun in elliptical orbits, with the sun positioned at one of the ellipse's foci. He was forced to dispose of the idea of circular planetary orbits, and had to reject the ancient belief that the planets traveled their orbits with a consistent speed.

What is the 3rd law of planetary motion?

Third law of Kepler
The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit. This captures the relationship between the distance of planets from the Sun, and their orbital periods.

What is Kepler's third law useful for?

Kepler's third law of planetary motion says that the average distance of a planet from the Sun cubed is directly proportional to the orbital period squared. Since Newton's law of gravity applies to any object with mass, Kepler's laws can be used for any object orbiting another object.

What is the formula for Kepler's 2nd law?

"Equal areas in equal times" means the rate at which area is swept out on the orbit (dA/dt) is constant. So Kepler's Second Law Revised: The rate at which a planet sweeps out area on its orbit is equal to one-half its angular momentum divided by its mass (the specific angular momentum).

What does p2 a3 mean?


4) Kepler's third law, p2 = a3, means that. A) the period of a planet does not depend on its mass. B) all orbits with the same semimajor axis have the same period. C) planets that are farther from the Sun move at slower average speeds than nearer planets.

What is the law of ellipses?

The law of ellipses is that the path of the planets about the sun is elliptical in shape, with the center of the sun being located at one focus.

Why is Kepler's third law called the harmonic law?

Harmonic Law Activity
Kepler's third law (the Harmonic Law), relates the orbital period of a planet (that is, the time it takes a planet to complete one orbit) to its mean distance from the Sun. This law states that the closest planets travel at the greatest speeds and have the shortest orbital periods.

What is the law of harmonies?

Kepler's third law - sometimes referred to as the law of harmonies - compares the orbital period and radius of orbit of a planet to those of other planets.

How do you calculate Kepler's third law?

If the size of the orbit (a) is expressed in astronomical units (1 AU equals the average distance between the Earth and Sun) and the period (P) is measured in years, then Kepler's Third Law says P2 = a3.

What is the theory of Kepler?


Kepler's three laws of planetary motion can be stated as follows: (1) All planets move about the Sun in elliptical orbits, having the Sun as one of the foci. (2) A radius vector joining any planet to the Sun sweeps out equal areas in equal lengths of time.

How did Kepler discover his first law?

Kepler's Laws of Planetary Motion
In 1605 he announced The First Law: Planets move in ellipses with the Sun at one focus. The figure below illustrates two orbits with the same semi-major axis, focus and orbital period: one a circle with an eccentricity of 0.0; the other an ellipse with an eccentricity of 0.8.

Where is the Earth when it is traveling the fastest?

The speed of the Earth is fastest when it is closest to the sun, in January, and slowest when it is farthest away from the sun, in July. In other words, in January it will be moving faster than average, and in July it will be moving slower than average.