waves

Related Questions

• A person carrying a whistle emitting continuously a note of 272 Hz is running towards a reflecting surface with a speed of 18 km/hour. The speed of sound in air is $345m{{s}^{-1}}$. The number of beats heard by him is

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• A stretched string of length $l,$ fixed at both ends can sustain stationary waves of wavelength $\lambda ,$ given by

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• A source of sound is moving with constant velocity of 20 m/s emitting a note of frequency 1000 Hz. The ratio of frequencies observed by a stationary observer while the source is approaching him and after it crosses him will be (Speed of sound v = 340 m/s)

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• Progressive wave of sound is represented by $y=a\sin [400\pi \,t-\pi x/6.85]$ where $x$ is in $m$ and $t$ is in sec. Frequency of the wave will be

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• Two tuning forks when sounded together produced 4 beats/sec. The frequency of one fork is 256. The number of beats heard increases when the fork of frequency 256 is loaded with wax. The frequency of the other fork is

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