The amplitudes of two waves are in the ratio $5 : 2$. If all other conditions for the two waves are the same,what is the ratio of their energy densities?

If the distance between the source and the screen is increased by $2\%$,what will be the effect on the intensity on the screen?

The dependence of disturbances due to two waves on time is shown in the figure. The ratio of their intensities $I_1 / I_2$ will be

$A$ surface of area $S$ is placed perpendicular to the direction of travel of a plane wave. The energy per unit time intercepted by the surface is $E$ when the amplitude of the wave is $A$. The area of the surface is reduced to $\frac{1}{2} S$ and the amplitude of the wave is increased to $2A$. What is the energy per unit time intercepted by this smaller surface?

The intensity of a sound wave while passing through an elastic medium falls by $10\%$ as it covers $1 \ m$ distance through the medium. If the initial intensity of the sound wave was $100 \ dB$,its value after it has passed through $3 \ m$ thickness of the medium will be .... $dB$.

Consider ten identical sources of sound,all emitting the same frequency but having random phase angles. If the average intensity of each source is $I_0$,what will be the average resultant intensity $I$ due to all these ten sources?