waves

Related Questions

• Frequency range of the audible sounds is

  ---

• A vehicle with a horn of frequency $n$ is moving with a velocity of 30 m/s in a direction perpendicular to the straight line joining the observer and the vehicle. The observer perceives the sound to have a frequency $n+{{n}_{1}}$. Then (if the sound velocity in air is 300 m/s)

  ---

• An observer moves towards a stationary source of sound of frequency n. The apparent frequency heard by him is 2n. If the velocity of sound in air is 332 m/sec, then the velocity of the observer is

  ---

• A wave is represented by the equation $y=7\sin \{\pi (2t-2x)\}$ where $x$ is in metres and $t$ in seconds. The velocity of the wave is

  ---

• A police car horn emits a sound at a frequency 240 Hz when the car is at rest. If the speed of the sound is 330 m/s, the frequency heard by an observer who is approaching the car at a speed of 11 m/s, is :

  ---