Name_______________________________ Date___________ Period_______
Universal Gravitation Assessment
Applying Concepts: Write the letter of the choice that best completes each statement.
_____1. During its orbital period, as a planet moves closer to the sun, the
orbital velocity of the planet ______________.
a. increases
b. decreases
c. remains the same
__________2. According to Newton’s law of universal gravitation, the force of
attraction between any two masses is directly related to the _____________.
a. distance between the masses
b. product of the two masses
c. velocity of the two masses
d. sum of the two masses
__________3. As the distance between two bodies increases, the force of attraction
between the bodies __________________.
a. increases
b. decreases
c. remains the same
__________4. Astronauts in an orbiting space shuttle experience a sensation of
weightlessness because ________________.
a.
b.
the space shuttle is falling freely toward Earth
the space shuttle is not affected by Earth’s gravity
c.
the mass of the space shuttle decreases as the distance from Earth increases
d.
the space shuttle is moving away from Earth.
__________5. Anything that has mass is surrounded by a ____________________.
a. satellite in orbit
c. gravitational field
b. magnetic field
d. black hole
__________6. The force of gravity exerts a
a. balanced force
b. centripetal force
on an orbiting satellite.
c. tangential force
d. All these are true.
___________7. The pair of spheres that experiences the greatest force of attraction is
.
Understanding Concepts Part B: Answer the following questions, showing your calculations.
8. Which of the pairs of masses below will have the greatest force of attraction between the
spheres?
9. Two spheres, each having a mass of 20.0 kg are positioned so that their centers are 8.00 m
apart. What is the gravitational force between the spheres?
10. If the mass of one of the spheres described in problem 2 were doubled, how far apart
would the spheres have to be to maintain the same gravitational force between them?
Applying Concepts: Answer the following quantities using complete sentences.
11. Earth is closer to the sun in December than it is in July. What happens to the orbital
speed of the planet between July and December? Explain your answer.
12. What would happen to the magnitude of the gravitational force between two bodies if:
a. the mass of one of the bodies were doubled?
b. the distance between the two bodies were doubled?
13. How does Einstein’s general theory of relativity account for the blackness of black holes
in the universe?
14. The mean distance between the center of Earth and the center of the moon is
3.84 X 108 m, and the moon has an orbital period of 27.3 days. Find the distance from Earth
of an artificial satellite that has an orbital period of 9.1 days.