Question

Newton's version of Kepler's Law Force Example Use what we know about the earth's orbit to estimate the mass of the sun. For this problem we can use Newton's form of Kepler's law Solving for the sum of the masses we get to use this law we need all our values to be kilograms, meters, and seconds. a 1AU-149.6x10P m and p- 1 year (365.25 days/year)(24 hours/day)(3600 seconds/hour)-3.15x 10" sec. Placing these values in to our equation we get M+ M 67 10 11 8.15 x 101 (149.6 x 10° M. + Me = 2 × 10 kg The mass of the earth is only about 6 x 10M kg so if we subtract that from the combined mass we would still have M,-2x 10 kg. So just by knowing the orbital properties we are able to find the masses of the orbiting bodies. Exercises: 1) Luke Skywalker observes a very small defense satellite orbiting the empire's "Death Star" at an average distance (from the center of the Death Star) of 75 km. What is the mass of the Death Star if the orbital period of the satellite is 3.0 hours? Be sure to show all your work clearly in order to receive credit. 2) 24 Navstar Satellites orbit the earth providing synchronized signals for GPS units here on earth. These Satellites orbit once every 12 hours. How far above the earth's surface are the Navstar satellites orbiting?

Answer 1

fin selo ni т 2. 3 IC. go 2 Once in ev 3 m= 5.47x10 y주2 at 39. 24 30000 Km) 930000-637/ 二 9a3G29km aw