Waves

### A SONAR system fixed in a submarine operates at a frequency kHz. An enemy submarine moves towards the SONAR with a speed of . What is the frequency of sound reflected by the submarine? Take the speed of sound in water to be .

Frequency of the SONAR system is given as $\mathrm{f}=40 \mathrm{kHz}=40 \times 10^{3} \mathrm{~Hz}$ Speed of sound in water is given as $v=1450 \mathrm{~m} / \mathrm{s}$ Speed of the enemy...

### A steel bar of length is nailed at its midpoint. The fundamental frequency of the longitudinal vibrations of the rod is . At what speed will the sound be able to travel through steel?

Length is given as $I=200 \mathrm{~cm}=2 \mathrm{~m}$ Fundamental frequency of vibration is given as, $\mathrm{v}_{\mathrm{F}}=2.53 \mathrm{kHz}=2.53 \times 10^{3} \mathrm{~Hz}$ The bar is then...

### A long pipe with a movable piston at one end and an opening at the other will be in resonance with a tuning fork vibrating at , if the length of the pipe is or . Calculate the speed of sound in air. Neglect the edge effects.

Frequency of the turning fork is given as $\mathrm{v}_{\mathrm{F}}=340 \mathrm{~Hz}$ Length of the pipe is given as $l_{1}=0.255 \mathrm{~m}$ Due to the presence of a piston at one end, the supplied...

### A transverse harmonic wave on a wire is expressed as: (i) Is it a stationary wave or a travelling one?ii) If it is a travelling wave, give the speed and direction of its propagation.[ and are in and in seconds. Assume the left to right direction as the positive direction of

Given function is, $(x, t)=3 \sin (36 t+0.018 x+\pi / 4)$ i) The equation of a progressive wave travelling from right to left is known as, $y(x, t)=a \sin (\omega t+k x+\Phi)$ On comparing equation...