Planetary Motion and Gravitation

Open Ended

How did Tycho Brahe contribute to our understanding of planetary motion?

Multiple Choice

Which scientist proposed that Earth and other planetary objects revolve around the Sun?

• Nicholas Copernicus

• Tycho Brahe

• Isaac Newton

• Galileo Galilei

Open Ended

Explain the significance of Kepler's first law in understanding planetary motion.

Multiple Choice

According to Kepler's second law, what does an imaginary line from the Sun to a planet sweep out in equal time intervals?

• Equal areas

• Equal distances

• Equal speeds

• Equal volumes

Multiple Select

Which of the following statements are correct about Kepler's laws?

• The paths of planets are ellipses with the Sun at one focus.

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

• The square of the ratio of the periods of two planets equals the cube of the ratio of their average distances from the Sun.

• All planets move in perfect circles around the Sun.

Open Ended

Europa, a satellite of Jupiter, has a period of 3.55 days. How many units is its radial distance?

Multiple Select

Which of the following factors would increase the gravitational force between two objects?

• Increasing the mass of one or both objects

• Decreasing the distance between the objects

• Decreasing the mass of both objects

• Increasing the distance between the objects

Multiple Choice

Which of the following statements best describes Newton's Law of Universal Gravitation?

• It states that objects attract each other with a force proportional to their masses and inversely proportional to the square of the distance between them.

• It states that only planets attract each other with a force proportional to their distance.

• It states that the force of attraction is independent of mass.

• It states that the force of attraction is proportional to the cube of the distance between objects.

Open Ended

Explain how Newton’s law of universal gravitation and Kepler’s third law are related in describing planetary motion.

Multiple Choice

What is the value of the universal gravitational constant G?

• 6.67 × 10^-11 N·m^2/kg^2

• 9.81 m/s^2

• 3.00 × 10^8 m/s

• 1.60 × 10^-19 C

Multiple Choice

According to Kepler’s first law, what is at the focus of a planet’s orbit?

• planet

• star

• Sun

• Moon

Multiple Choice

In the equation for Kepler’s third law, what should be in place of the x?

• 1

• 2

• 3

• 4

Multiple Choice

Which two factors is the gravitational force between two objects dependent upon?

• mass, distance

• weight, force

• velocity, mass

• acceleration, mass

Open Ended

How does the inverse square law relate to the law of universal gravitation and what does the graph tell us about the relationship between force and distance?

Open Ended

Summarize one new thing you learned about planetary motion and gravitation in this lesson.

Open Ended

What role does gravity play in planetary motion?