6.17. Set Up: A proton has mass Solve: 6.18. Set Up: The net force on each astronaut is the gravity force exerted by the other astronaut. Call the astronauts A and B , where and Solve: (a) The free-body diagram for astronaut A is given in Figure 6.18a and for astronaut B in Figure 6.18b. for A gives and And for B , (b) gives and so and (c) Their accelerations would increase as they moved closer and the gravitational attraction between them increased. Figure 6.18 6.19. Set Up: The gravitational force between two objects is The mass of the earth is and the mass of the sun is The distance from the earth to the sun is and the distance from the earth to the moon is Solve: It is more accurate to say the moon orbits the sun. Reflect: The sun is farther away but has a much greater mass than the earth. 6.20. Set Up: The gravitational force is where r is the distance of the satellite from the center of the earth. so Solve: The weight of the satellite at the earth’s surface is so of w . F g 5 79.1%
This is the end of the preview.
access the rest of the document.