Worked Example 02
The Question
Because of your knowledge of physics and interest in the environment, you have gotten a summer job with an organisation which wants to orbit a satellite to monitor the amount of chlorine ions in the upper atmosphere over Australia. It has been determined that the satellite should collect samples at a height of 100 km above the Earth's surface. Unfortunately, at that height air resistance would make the amount of time the satellite would stay in orbit too short to be useful. You suggest that an elliptical orbit would allow the satellite to be close to the Earth over Australia, where data was desired, but farther from the Earth, and thus out of almost all of the atmosphere, on the other side of our planet. Your colleague estimates that the satellite would be traveling at 10,000 km/hour when it was farthest from the Earth at a height of 1,000 km. How fast would the satellite be traveling when it took its air samples if you neglect air friction?
The Answer
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