Kepler’s first law of planetary motion says that the paths of the planets are A. Parabolas B. Hyperbolas C. Ellipses D. Circles Ans: C
A planet orbiting the sun a. Maintains the same distance from the sun b. Moves at a constant speed c. Moves faster when it is farther from the sun d. Moves faster when it is closer to the sun Ans: D
Newton’s law of universal gravitation states that the gravitational force between two bodies is A. Directly proportional to the distance between them B. Directly proportional to the square of the distance between them C. Inversely proportional to the distance between them D. Inversely proportional to the square of the distance between them Ans: D
Two moons orbit a planet. The average orbital radius of the outer moon is 1.8 times that of the inner moon. The orbital period of the outer moon is a times that of the inner moon b. 1.8 times that of the inner moon c. 2.4 times that of the inner moon d. 5.8 times that of the inner moon Ans: C
The center of mass A of an object is 0.48 m from the center of mass B of another object. How much greater would the gravitational force between the two masses be if their centers were only 0.12 m apart? A. 2 times greater B. 4 times greater C. 8 times greater D. 16 times greater Ans: D
The mass of Earth is approximately 6.0 x kg. What would the acceleration due to gravity be on the surface of planet Q which has a mass of 5.0 x kg and a radius equal to the radius of Earth? A. 6.8 m/s 2 B. 8.2 m/s 2 C. 9.8 m/s 2 D. 12 m/s 2 Ans: B
Two satellites orbit the Earth at the same altitude in circular orbits. One satellite has a mass of 450 kg, and the other has a mass of 150 kg. The orbital speed of the larger satellite is A. The same as the speed of the smaller satellite B. 1.7 times the speed of the smaller satellite C. 3.0 times the speed of the smaller satellite D. 9.0 times the speed of the smaller satellite Ans: A
What is the acceleration due to gravity at an altitude of 4.0 Earth radii above the surface of Earth? A m/s 2 B. 2.0 m/s 2 C. 2.4 m/s 2 D. 9.8 m/s 2 Ans: A
Two cans of soda are next to each other on a table. If the mass of each can of soda is kg and their centers are 0.08 m apart, what is the gravitational force between them? A. 20 N B. 2.0 x N C. 1.3 x N D. 1.3 x N Ans: C
Suppose that in the distant future, astronauts are exploring a planet in another solar system. They find that the radius of the planet is 7.8 x 10 3 km and the acceleration due to gravity on its surface is 12.3 m/s 2. What is the mass of the planet? A. 1.1 x kg B. 6.0 x kg C. 1.1 x kg D. 6.0 x kg Ans: C
A satellite orbits Earth 3,250,000 m above the Earth’s surface. What is the satellite’s orbital speed? A m/s B m/s C m/s D m/s Ans: A
A satellite orbits a planet in a circular orbit. If the orbital radius is 7.8 x 10 8 m and the time required for a complete revolution is 3.5 x 10 6 S, what is the orbital speed? A. 140 m/s B m/s C m/s D m/s E m/s Ans: E