Home
Class 9
PHYSICS
In a certain gas, a source produces 40,0...

In a certain gas, a source produces 40,000 compression and 40,000 rarefaction pulses in 1 sec. When the second compression pulse is produced, the first is 1cm away from the source. Calculate the wave speed.

Text Solution

Verified by Experts

We know frequency is equal to number of compression or rarefaction pulses travelled per second, hence frequency `(upsilon)=40,000` Hz
Wave length `(lambda)=` distance between two consecutive compression or rarefaction pulses.
`lambda=1` cm
From `v= upsilon lambda = 40,000 Hz xx 1 cm= 40,000 cm//s=400 m//s`
Promotional Banner

Topper's Solved these Questions

  • SOUND

    NCERT BANGLISH|Exercise Think and Discuss|12 Videos

  • SOUND

    NCERT BANGLISH|Exercise Let us Improve our learning ( Reflections on concepts)|6 Videos

  • REFRACTION OF LIGHT AT PLANE SURFACES

    NCERT BANGLISH|Exercise THINK AND DISCUSS|2 Videos

  • WHAT IS INSIDE THE ATOM ?

    NCERT BANGLISH|Exercise THINK AND DISCUSS|1 Videos

Similar Questions

Explore conceptually related problems

A source of sound produces 20 compressions and 20 rarefaction in 0.2 seconds. The distance between a compression and the consecutive rerefaction is 50 cm. Find the wavelength, frequency and time-period of the wave.

Two straight and parallel slits 0.4 mm apart , are illuminated by a source of monochromatic light. Interfer- ence patter of fringe width 0.5 mm is produced 40 cm away from the slits . Find the wavelength of the light used.

Einstein established the idea of photons on the basis of Planck's quantum theory. According to his idea, the light of frequency f or wavelength lamda is infact a stream of photons. The rest mass of each photon is zero and velocity is equal to the velocity of light (c) = 3 xx 10^(8) m.s^(-1) . Energy, E = hf, where h = Planck's constant = 6.625 xx 10^(-34)J.s . Each photon has a momentum p = (hf)/(c) , although its rest mass is zero. The number of photons increase when the intensity of incident light increases and vice-versa. On the other hand, according to de Broglie any stream of moving particles may be represented by progressive waves. The wavelength of the wave (de Broglie wavelength) is lamda = (h)/(p) , where p is the momentum of the particle. When a particle having charge e is accelerated with a potential difference of V, the kinetic energy gained by the particle is K= eV. Thus as the applied potential difference is increased, the kinetic energy of the particle and hence the momentum increase resulting in a decrease in the de Broglie wavelength. Given, charge of electron, e = 1.6 xx 10^(-19)C and mass = 9.1 xx 10^(-31) kg . The number of photons emitted per second from a light source of power 40 W and wavelength 5893 Å

A tuning fork of unknown frequency produces 5 beats per second with another tuning fork. The second fork can cause a closed organ pipe of length 40 cm to vibrate in its fundamental mode. The beat frequency decreases when a small amount of wax is dropped on the first fork. Find out the frequency of the first tuning fork. Given, speed of sound in air = 320 m * s^(-1) .