Physics 1.25: Planetary Motion Review

Kepler's _____ Law states that the paths of the planets are ellipses, with the Sun at the center.

• 1st

• 2nd

• 3rd

• 4th

"An imaginary line from the Sun to a planet sweeps out equal areas in equal time intervals" is...

• Kepler's 1st Law

• Newton's 2nd Law

• Kepler's 2nd Law

• Newton's 3rd Law

The gravitational force between two massive spheres

• is always an attraction.
• depends on how massive they are.
• depends inversely on the square of the distances betwn them.
• all of the above

A massive object and a less massive object exert a gravitational force on each other. Which of the following picture correctly shows the magnitude and direction of the forces involved in this interaction?

• 
• 
• 
• 

The gravitational force in the previous interaction was 20 N. Determine the gravitational force in the new situation where the second mass is doubled.

• 10 N

• 20 N

• 40 N

• 80 N

The distance between the two masses in the previous situation is halved. Determine the gravitational force in this new situation.

• 20 N

• 40 N

• 80 N

• 160 N

Which of the following is Newton's Law on Gravitation?

• F=Gm₁m₂/r
• F = Gm₁m₂/r²
• F = Gm₁m₂/2r
• F = m₁m₂/2r

A satellite moves ______________when it is moved farther from the object that it orbits.

• more quickly
• more slowly
• at the same speed
• with no change in speed

Kepler's First Law states

• objects attract other objects with a force that is directly proportional to the product of their masses

• the square of the ratio of the periods of any two planets revolving around the Sun is equal to the cube of the ratio of their average distance from the Sun

• An imaginary line joining a planet and the sun sweeps out an equal area of space in equal amounts of time.

• Planets move about the Sun in an elliptical orbit with the Sun at one of the foci.

Kepler's Second Law states

• objects attract other objects with a force that is directly proportional to the product of their masses

• the square of the ratio of the periods of any two planets revolving around the Sun is equal to the cube of the ratio of their average distance from the Sun

• An imaginary line joining a planet and the sun sweeps out an equal area of space in equal amounts of time.

• Planets move about the Sun in an elliptical orbit with the Sun at one of the foci.