Kepler's Laws

What shape do the orbits of planets around the sun have according to Kepler's First Law?

• Circle

• Ellipse

• Parabola

• Hyperbola

Kepler's Second Law, also known as the Law of Equal Areas, states that a line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time. This implies that the planet moves __________.

• at a constant speed

• faster when it is closer to the Sun

• slower when it is closer to the Sun

• in a straight line

• The square of the orbital period is directly proportional to the cube of the semi-major axis.

• The orbital period is directly proportional to the semi-major axis.

• The square of the orbital period is inversely proportional to the cube of the semi-major axis.

• The orbital period is inversely proportional to the semi-major axis.

What is the orbital eccentricity of a circular orbit?

• 0

• 0.5

• 1

• Undefined

Which of the following best describes orbital eccentricity?

• The time it takes for a planet to complete one orbit around the Sun

• The distance between a planet and the Sun

• A measure of how an orbit deviates from a circle

• The speed of a planet in its orbit

According to Kepler's First Law, where is the Sun located in relation to a planet's orbit?

• At the exact center of the orbit

• At one of the foci of the elliptical orbit

• Outside the orbit

• At the highest point of the orbit

Kepler's Third Law can be used to calculate which of the following?

• The mass of the Sun

• The size of the orbit of a planet

• The time it takes for a planet to orbit the Sun

• The speed of a planet in its orbit

If the semi-major axis of a planet's orbit is doubled, by what factor does the orbital period change according to Kepler's Third Law?

• Increases by a factor of 2

• Increases by a factor of 4

• Increases by a factor of 8

Which of the following is NOT a direct consequence of Kepler's laws?

• Planets closer to the Sun orbit faster than those further away.

• All planets move in elliptical orbits with the Sun at one focus.

• The orbits of planets are perfectly circular.

• The area swept by the line segment joining a planet and the Sun in a given time is constant.

What is the significance of the eccentricity being close to 1 for an orbit?

• The orbit is nearly circular.

• The orbit is highly elliptical.

• The orbit is parabolic.

• The orbit is hyperbolic.