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Doppler Shift

Velocity, frequency of sound

1.A supersonic jet traveling at Mach 3 at an altitude of 20000m is directly overhead at time t=0. A) How long will it be before the ground observer encounters the shock wave? B)Where will the plane be when it is finally heard?(Assume an average value of 330m/s for speed of sound in air) I will send what I have for this one

Calculating sound waves, wavelength shift in regards to the Doppler Effect.

A sound detector is placed on a railway platform. A train, approaching the platform at a speed of 36km/h sounds its whistle. The detector detects 12 kHz as the most dominant frequency in the whistle. If the train stops at the platform and sounds the whistle, what would be the most dominant frequency detected? The speed of sound

Sound Waves

The ear has a protective overload mechanism called the "acoustic reflex". A sound in excess of about 85 dB causes muscles attached to the eardrum and ossicles to engage, which provides a safety margin of about 20 dB or 30 dB (the equivalent of ear plugs). This reflex takes about 30 ms to 40 ms to cut in, and maximum effect only