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(Solved): 1 Problem Johannes Kepler first discovered that the planets move in elliptical orbits around the Su ...
1 Problem Johannes Kepler first discovered that the planets move in elliptical orbits around the Sun. Satellites orbit the earth in a similar way. Consider the image below wherein a satellite is moving along an elliptical orbit with a semi-minor axis a=13,860km and semi-major axis b=16,000km with the earth located at one focus of the ellipse with c=8,000km. At the instant shown the satellite has a velocity v=17,970km/h. The acceleration of the satellite is purely due to gravity in the direction pointing from A to the center of the earth. In general, gravitational acceleration follows an inverse square law. While the acceleration of gravity on the surface of the earth (radius of earth re?=6,371) has magnitude ge?=9.821m/s2 the acceleration at point A is gA?=ge?(re?/r)2. Derive a symbolic expression for the radius of curvature ? and the rate of change of speed v? of the orbit at A as a function of the parameters of the problem using a path frame. (You can check your answer by plugging in the numerical values to confirm that ?=18,480km. Note: e^n? is pointing straight down in this problem - not towards the center of the earth.) 2 Problem Repeat the problem above and determine r?,r¨,??,?¨ at the instant shown. Assume that ? is measured counter clockwise from the horizontal line passing through the center of the earth.