Submarine A travels horizontally at 11.0 m/s through ocean water. It emits a sonar signal of frequency f 5 5.27 3 103 Hz in the forward direction. Submarine B is in front of submarine A and traveling at 3.00 m/s relative to the water in the same direction as submarine A. A crewman in submarine B uses his equipment to detect the sound waves (pings) from submarine A. We wish to determine what is heard by the crewman in submarine B. (a) An observer on which submarine detects a frequency f 9 as described by Equation 17.19? (b) In Equation 17.19, should the sign of vS be positive or negative? (c) In Equation 17.19, should the sign of vO be positive or negative? (d) In Equation 17.19, what speed of sound should be used? (e) Find the frequency of the sound detected by the crewman on submarine B.
Rosanna Cheng PH 106 02.17.17 and 02.23.17 Pages 560-580 Reading Journal Prediction The chapter will continue to discuss magnetism. Notes 20.1 Magnets and Magnetic Fields * Poles are the ends/faces of a magnet. The pole of a freely suspended magnet pointing toward north is north pole. The other is south pole. Like poles repel, unlike poles attract. Magnetic monopole doesn’t exist, as of now. Ferromagnets are made of iron and show strong magnetic effects. Magnetic fields are like electric fields, with magnetic field lines like electric field lines. However, the m.f. lines always form closed loops. Earth’s geographic poles are different from the magnetic poles: north is magnetically a south pole. Magnetic declination is the angular difference between the dir
