Question

1 point
(13) Under normal working
conditions, radio, loudspeakers,
industrial machinery and
children in play ground all
produce sound waves, under
the same air conditions, all
these sound waves
have the same amplitude
have the same frequency
have the same wavelength
travel with same speed​

Answer 1

Answer:

While pure constructive and pure destructive interference do occur, they require precisely aligned identical waves. The superposition of most waves produces a combination of constructive and destructive interference, and can vary from place to place and time to time. Sound from a stereo, for example, can be loud in one spot but quiet in another. Varying loudness means the sound waves add partially constructively and partially destructively at different locations. A stereo has at least two speakers creating sound waves, and waves can reflect from walls. All these waves superimpose. An example of sounds that vary over time from constructive to destructive is found in the combined whine of airplane jets heard by a stationary passenger. The combined sound can fluctuate up and down in volume as the sound from the two engines varies in time from constructive to destructive.