InterviewSolution
Saved Bookmarks
| 1. |
Two audio speakers are kept some distance apart and are driven by the same amplifier system. A person is sitting at a place 6.0 m from one of the speakers and 6.4 m from the other. If the sound signal is continuously varied from 500 Hz to 5000 Hz, what are the frequencies for which there is a destructive interference at the place of the listener? Speed of sound in air` = 320 ms^-1` |
|
Answer» Correct Answer - A::B::C::D The path difference of the two sound waves is given by `/_L=6.4-6.0=0.4m` The wavelength of either wave `lamda=V/p=320/p (m/s)` For destructive inteference `/_L=(2n+1)lamda/2` where n is an integers `or 0.4m =2+1/2xx320/p` `rarr p=n=320/0.4` `=800 (2n+1)/2 Hz` `=(2n+1)400Hz` Thus the frequency within the specified range which cause detructive inteference are 1200 Hz, 2000 Hz, 2800Hz, 3600Hz and 4400 Hz.` |
|