A Battery-operated toy emites a signal at 1800Hz. It moves in a circle of a radius 1.2 m at 2.4 revolutions per seconds. What are the minimium and maximum frequencies heard by a stationary observer some distance away in the plane of the circle? Assume the speed of sound is 330 ms-1
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
A student in a parked car honks the horn, which has a `proper' frequency of 300 Hz. An observer in an approaching vehicle measures the frequency of the sound to be 329 Hz. Calculate the speed of the approaching vehicle. Use 343 m/s as the speed of sound in air.
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
The radar speed trap operates on a frequency of 10^9 Hz. What is the beat frequency between the transmitted signal and one received after reflection from a car moving at 30 m/sec?
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