Homework 2
Answers are due by 5:00 pm Monday.
######### SATELLITES AND ORBITS ##########
Q1> A satellite in a true geosynchronous orbit has a period of 86,164 seconds. Why not 86,400 seconds???
Q2> A weather satellite is placed in a geosynchronous orbit above Earth's equator. Using Kepler's Law of Periods (given in class - also online notes), determine what parts of the earth the satellite cannot observe by direct line of sight (neglecting atmospheric refraction) and explain why. For the purposes of this problem, consider the earth to be a sphere with a radius of 6371 km. Hint: Remember the relationship between a sphere's radius and its tangent. Try drawing a diagram.
Q3> Explain, in two sentences or less, the physical reason why it's not feasible for a single satellite based sensor to provide continuous surveillance of an individual person (even in an open, cloud-free area).
Q4> For a flight to Mars, a rocket is launched in the direction the earth is moving in its orbit about the sun. For a flight to Venus, it is launched in the direction opposite of the earth's orbit. Why?? Hint - think about the implications of changing "P" in Kepler's Law of Periods.
Q5> Considering the variables given in the equation governing the decay of a satellite orbit (see class notes), what fundamental physical process causes orbits to decay? The answer can be given in a single word.
Extra Credit> Why do satellites burn up upon reentry into Earth's atmosphere if rockets do not burn up when they pass through the atmosphere on their way into orbit?