1. A 2150 kg satellite used in a cellular telephone network is in a circular orbit at a height of 780 km above the surface of the earth. What is the gravitational force on the satellite? What fraction is this of its weight at the surface of the earth?

2. Calculate the magnitude and direction of the net gravitational force on the moon due to the earth and the sun when the moon is in each of the positions shown in Fig. (Note that the figure is not drawn to scale. Assume that the sun is in the plane of the earth-moon orbit, even though this is usually not the case.) Use the data in Appendix F.

3. Gravitational Field. The gravitation field produced by an object is defined as F^→_g the gravitational force that the object exerts on a small test particle of mass m divided by m. That is g^→= F^→_g / m. What are the magnitude and direction of the gravitational field produced by a 20.0 kg spherically symmetric object at a point 1.50m directly above the center of the object?