GPS Transmission. The GPS (Global Positioning System) satellites are approximately 5.18 m across and transmit two low-power signals, one of which is at 1575.42 MHz (in the UHF band). In a series of laboratory tests on the satellite, you put two 1575.42-MHz UHF transmitters at opposite ends of the satellite. These broadcast in phase uniformly in all directions. You measure the intensity at points on a circle that is several hundred meters in radius and centered on the satellite. You measure angles on this circle relative to a point that lies along the centerline of the satellite (that is, the perpendicular bisector of a line that extends from one transmitter to the other). At this point on the circle, the measured intensity is 2.00 W/m2. (a) At how many other angles in the range 0° < θ < 90° is the intensity also 2.00 W/m2? (b) Find the four smallest angles in the range 0° < θ < 90° for which the intensity is 2.00 W/m2. (c) What is the intensity at a point on the circle at an angle of 4.65° from the centerline?
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