Chapter 5: Circular Motion and Gravity

1. Chapter 5: Circular Motion and Gravity

2. A ball is whirled in a horizontal circle of radius r and speed v. The radius is increased to 2r keeping the speed of the ball constant. The period of the ball changes by a factor of • one half. • one. • two. • three. • four.

3. A ball is whirled in a horizontal circle of radius r and speed v. The radius is increased to 2r keeping the speed of the ball constant. The period of the ball changes by a factor of • one half. • one. • two. • three. • four.

4. The figure shows the position of a ball as it is being whirled in a vertical circle. At point (a), the direction of the centripetal acceleration is

5. The figure shows the position of a ball as it is being whirled in a vertical circle. At point (a), the direction of the centripetal acceleration is

6. Suppose a planet exists that has half the mass of earth and half its radius. On the surface of that planet, the acceleration due to gravity is • twice that on Earth. • the same as that on Earth. • half that on Earth. • one-fourth that on Earth. • none of these.

7. Suppose a planet exists that has half the mass of earth and half its radius. On the surface of that planet, the acceleration due to gravity is • twice that on Earth. • the same as that on Earth. • half that on Earth. • one-fourth that on Earth. • none of these.

8. The radius R of a stable, circular orbit for a satellite of mass m and velocity v about a planet of mass M is given by • R = Gv/M • R = Gv/mM • R = GmM/v • R = GM/mv • R = GM/v2

9. The radius R of a stable, circular orbit for a satellite of mass m and velocity v about a planet of mass M is given by • R = Gv/M • R = Gv/mM • R = GmM/v • R = GM/mv • R = GM/v2

10. As a satellite falls into a lower orbit, its speed • decreases. • is unchanged. • increases. • depends on the mass of the satellites. • cannot be determined.

11. As a satellite falls into a lower orbit, its speed • decreases. • is unchanged. • increases. • depends on the mass of the satellites. • cannot be determined.

12. Which of the following statements is one of Kepler's three laws of planetary motion? • A line joining any planet to the sun sweeps out equal areas in equal times. • Only an odd number of planets can orbit the sun. • The period of any planet about the sun is proportional to the planet's distance from the sun. • All planets move in elliptical orbits with the earth at one focus. • F = GMm/R2

13. Which of the following statements is one of Kepler's three laws of planetary motion? • A line joining any planet to the sun sweeps out equal areas in equal times. • Only an odd number of planets can orbit the sun. • The period of any planet about the sun is proportional to the planet's distance from the sun. • All planets move in elliptical orbits with the earth at one focus. • F = GMm/R2

14. Of the satellites shown revolving around Earth, the one with the greatest speed is • 1 • 2 • 3 • 4 • 5

15. Of the satellites shown revolving around Earth, the one with the greatest speed is • 1 • 2 • 3 • 4 • 5

16. Five masses are in orbit around a central mass. A is a distance R from the center, B is at 2R, C is at 3R, D at 4R and E is at 5R. Which planet has the longest period of revolution?

17. Five masses are in orbit around a central mass. A is a distance R from the center, B is at 2R, C is at 3R, D at 4R and E is at 5R. Which planet has the longest period of revolution?

18. A planet is orbiting a star in an elliptical orbit as shown. The speed of the planet when it is at A is _____ the speed when it is at B. • less than • equal to • greater than

19. A planet is orbiting a star in an elliptical orbit as shown. The speed of the planet when it is at A is _____ the speed when it is at B. • less than • equal to • greater than