3. The frequency of a tornado siren is 1,000 Hz. If a cyclist is moving toward the siren at 10 m/s in 15 °C air, which has a speed of sound of 340 m/s, what is the frequency that the cyclist observes? V=V f = f obs source V=V Sobe = ? I source V source questions continued on next page Unit 6C Practice Problems Copyright 2018 Georgia Public Broadcasting. All rights reserved. Use or distribution by an unintended recipient is prohibited.

(a) Seismographs measure the arrival times of earthquakes with a precision of 0.100 s. To get the distance to the epicenter of the quake, geologists compare the arrival times of S- and P-waves, which travel at different speeds. If S- and P-waves travel at 4.00 and 7.20 km/s, respectively, in the region considered, how precisely can the distance to the source of the earthquake be determined? (b) Seismic waves from underground detonations of nuclear bombs can be used to locate the test site and detect violations of test bans. Discuss whether your answer to (a) implies a serious limit to such detection. (Note also that the uncertainty is greater if there is an uncertainty in the propagation speeds of the S- and P-waves.)

Wind gusts create ripples on the ocean that have a wavelength at 5.00 cm and propagate at 2.00m/s. What is their frequency?

An airplane moves at Mach 1.2 and produces a shock wave. (a) What is the speed of the plane in meters per second? (b) What is the angle that the shock wave moves?