Lesson 7.2 "Using the Law of Universal Gravitation"

Multiple Choice

Why is it important to understand that all objects are surrounded by a gravitational field that affects the motions of other objects?

• Because it helps us predict the movement of planets and satellites.

• Because it explains why objects fall to the ground.

• Because it helps us understand the concept of weight.

• Because it is necessary for space travel.

Open Ended

How can you describe orbital motion?

Multiple Choice

Which of the following best describes the difference between inertial mass and gravitational mass?

• Inertial mass is related to an object's resistance to acceleration, while gravitational mass determines the strength of gravitational attraction.

• Inertial mass determines the strength of gravitational attraction, while gravitational mass is related to resistance to acceleration.

• Both inertial mass and gravitational mass are unrelated to gravity.

• Inertial mass and gravitational mass are always equal by definition.

Multiple Select

Which of the following quantities are independent of the mass of a satellite orbiting Earth?

• Orbital speed

• Orbital period

• Orbital radius

• Both orbital speed and period

Open Ended

Explain how the Law of Universal Gravitation is involved in determining the orbits of planets and satellites.

Fill in the Blanks

Engineers are planning to place a space station into orbit at an altitude of 450 km above Earth’s surface. What would be the orbital speed and period of the station?

Open Ended

Describe why astronauts in a space shuttle experience weightlessness even though Earth's gravitational force is still present.

Fill in the Blanks

At an altitude of about 400 km above Earth’s surface, the acceleration due to gravity is

m/s².

Multiple Choice

Which of the following best describes the gravitational field around an object with mass?

• It acts only when objects are touching.

• It acts over a distance and surrounds any object with mass.

• It only affects objects with no mass.

• It is measured in kg/m.

Open Ended

Explain the difference between inertial mass and gravitational mass, and discuss why Newton and Einstein considered their equivalence important.

Multiple Select

Which of the following statements are true about Einstein’s theory of gravity?

• Gravity is a force between two objects.

• Mass causes space to be curved.

• Einstein’s theory predicts how massive objects affect one another.

• Einstein’s theory has never been tested.

Fill in the Blanks

According to Einstein’s theory, objects that are so massive and dense that no light escapes are called

.

Multiple Choice

Which of the following best describes the difference between gravitational mass and inertial mass?

• Gravitational mass determines the strength of gravitational force, while inertial mass determines resistance to acceleration.

• Gravitational mass and inertial mass are exactly the same in all contexts.

• Inertial mass determines the strength of gravitational force, while gravitational mass determines resistance to acceleration.

• Gravitational mass only applies to objects on Earth, while inertial mass applies everywhere.

Open Ended

Reflecting on what you learned about gravitational fields, how do you think gravitational fields affect the motion of objects in space?