A sound absorber attenuates (decreases) sound level by 20, dB . intensity decreases by a factor of

English

Gujarati

Hindi

14.Waves and Sound

normal

A sound absorber attenuates (decreases) the sound level by $20\, dB$. The intensity decreases by a factor of

$100$

$1000$

$10000$

$10$

Solution

$\mathrm{L}_{1}=10 \log \left(\frac{\mathrm{I}_{1}}{\mathrm{I}_{0}}\right) ; \quad \mathrm{L}_{2}=10 \log \left(\frac{\mathrm{I}_{2}}{\mathrm{I}_{0}}\right)$

$\therefore \mathrm{L}_{1}-\mathrm{L}_{2}=10 \log \left(\frac{\mathrm{I}_{1}}{\mathrm{I}_{0}}\right)-10 \log \left(\frac{\mathrm{I}_{2}}{\mathrm{I}_{0}}\right)$

or $\quad \Delta \mathrm{L}=10 \log \left(\frac{\mathrm{I}_{1}}{\mathrm{I}_{2}}\right) \quad$ or $\quad 20 \mathrm{dB}=10 \log \left(\frac{\mathrm{I}_{1}}{\mathrm{I}_{2}}\right)$

or $10^{2}=\frac{I_{1}}{I_{2}}$ or $I_{2}=\frac{I_{1}}{100}$

Standard 11

Physics

In a standing wave on a string rigidly fixed at both ends

normal

In a Fraunhofer's diffraction obtained by a single slit aperture, the value of path difference for $n^{th}$ order of minima is

normal

The diagram shows snapshot of a wave at time $t = 0$. The particle at $x = x_1$ is moving upward at that instant. Direction of propagation of wave is

normal

Two cars $A$ and $B$ are moving in the same direction with speeds $36\,km/hr$ and $54\,km/hr$ respectively. Car $B$ is ahead of $A$. If $A$ sounds horn of frequency $1000\,Hz$ and the speed of sound in air is $340\,m/s$, the frequency of sound received by the driver of car $B$ is ……………… $\mathrm{Hz}$

normal

A transverse wave is described by the equation $y = {y_0}\,\sin \,2\pi \,\left[ {ft – \frac{x}{\lambda }} \right]$ . The maximum particle velocity is equal to four times the wave velocity if

normal

A sound absorber attenuates (decreases) the sound level by $20\, dB$. The intensity decreases by a factor of

Solution

Similar Questions

In a standing wave on a string rigidly fixed at both ends

In a Fraunhofer's diffraction obtained by a single slit aperture, the value of path difference for $n^{th}$ order of minima is

The diagram shows snapshot of a wave at time $t = 0$. The particle at $x = x_1$ is moving upward at that instant. Direction of propagation of wave is

A transverse wave is described by the equation $y = {y_0}\,\sin \,2\pi \,\left[ {ft – \frac{x}{\lambda }} \right]$ . The maximum particle velocity is equal to four times the wave velocity if

Start a Free Trial Now