The wavelength is 120 cm when the source is stationary. If the source is moving with velocity of 60 m/sec towards the stationary observer, then the wavelength of the sound wave reaching to the observer will be :–

(velocity of sound = 330 m/s)

The driver of a car travelling with speed 30 m/s towards a hill sounds a horn of frequency 600 Hz. If the velocity of sound in air is 330 m/s, the frequency of reflected sound heard by driver is :

A string 2.0 m long and fixed at its both ends is driven by a 240 Hz vibrator. The string vibrates in its third harmonic mode. The speed of the wave and its fundamental frequency is :–

A string of length 1m and mass 5g is fixed at both the ends. The tension in the string is 8.0 N. The string is set into vibration using an external vibrator of frequency 100 Hz. The separation between successive nodes on the string is close to

A one metre long (both ends open) organ pipe is kept in a gas that has double the density of air at STP assuming the speed of sound in air at STP is 300 m/s. The frequency difference between the fundamental and second harmonic of this pipe is

A wave pulse in thin string is incident on a thick string as shown in the figure. If joint is at P, then the form of reflected and transmitted pulses is :

If λ₁, λ₂, λ₃ are the wave lengths of wave giving resonance with the fundamental, first and second overtones respectively of a close organ pipe then ratio of wavelengths λ₁ : λ₂ : λ₃ is :

Two stretched strings of same material are vibrating under same tension in fundamental mode. The ratio of their frequencies is 1 : 2 and ratio of vibrating length is 1 : 4. Then the ratio of radii of the string is :

A Train approaches stationary observer, with velocity 1/20 of the velocity of sound. A sharp blast is blown with the whistle of the engine at equal intervals of one second. The interval between blasts as heard by the observers.

A source of sound is travelling at 100/3 m/s along a road, towards a point A. when the source S is 3 m away from A, person standing at a point O on a road perpendicular as shown. The distance of O from A at that time is 4 m. If original frequency is 640 Hz, then the value of apparent frequency for the person is (given velocity of sound = 340 m/s)