Sweigart: Kepler's Laws

Front

What are Kepler's Laws of Planetary Motion?

Back

Kepler's Laws describe the motion of planets around the Sun: 1) Planets move in elliptical orbits with the Sun at one focus. 2) A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. 3) The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.

Front

What shape do planets' orbits take according to Kepler's First Law?

Back

Elliptical.

Front

What does Kepler's Second Law state about a planet's speed?

Back

A planet moves faster when it is closer to the Sun and slower when it is farther from the Sun.

Front

What is the significance of the Sun in a planet's elliptical orbit?

Back

The Sun is located at one of the foci of the elliptical orbit.

Front

What is the relationship between a planet's distance from the Sun and its orbital period according to Kepler's Third Law?

Back

The farther a planet is from the Sun, the longer it takes to complete one orbit.

Front

Which planet takes the longest time to orbit the Sun?

Back

Mars.

Front

What is the term for the point in a planet's orbit where it is closest to the Sun?

Back

Perihelion.

Front

What is the term for the point in a planet's orbit where it is farthest from the Sun?

Back

Aphelion.

Front

How does the area swept by a planet in its orbit relate to time?

Back

The area swept out by a planet in its orbit is equal for equal time intervals.

Front

What is the implication of Kepler's laws for predicting planetary positions?

Back

Kepler's laws allow us to predict the positions of planets at any given time based on their orbital characteristics.