Kepler's Laws-Notes Flashcards
What is the Law of Ellipses? (Kepler’s First Law)
States that Planets travel around the sun in an elliptical path. An ellipse is a geometric shape with 2 foci.
What is the law of equal areas? (Kepler’s Second Law)
States that the imaginary line that connects the sun and the planet keeps equal areas of space during specific time intervals. Planets move faster when closest to the sun and slower when far away from the sun.
What is the Law of Harmonies? (Kepler’s third Law)
States that there is a relationship beteen the time it takes for a planet to go around the sun (T) and the semi-major Axis (R). In other words: T squared= R cubed.
Define Ellipse
Geometric shape with 2 Foci instead of 1 fous
Define Perihelion
When a planet is closest to the sun
Define Aphelion
When a planet is farthest from the sun
Define the Major Axis
Distance from the Perihelion to the Aphelion
Define the Semi-Major Axis
Half the distance of the major axis. Represents by the letter (R). It is the average distance from the planet to the sun.
Define the Minor Axis
The shorter axis of an ellipse that is perpendicular to the major axis.
Define Eccentricity
Distance from the center of the ellipse to either focus divided by the semi-major axis (R). The closer to zero the more circular the ellipse. The closer to one, the more squashed the ellipse.
Define Astronomical Unit
Average distance from the sun to Earth. Used as a unit of measurement for distance in the solar system.
What does the dashed horizontal line in a diagram represent?
Major Axis
What does the Vertical line in a diagram represent?
Minor Axis
What does the solid horizontal line in a diagram represent?
Semi-Major Axis
What does R represent?
Semi-Major Axis
What does P represent?
The Perihelion
What does T represent?
The Oribtal Time around the sun
How is distance labeled?
Astronomical Units
How is time labeled?
Years
How is eccentricity labeled?
Has no Units
How do you solve Kepler’s third law when given the Astronomical Units ONLY. (T squared=R cubed)?
Cube the Astronomical Units in the equation first, then find the square root of it.
