Sound waves are not transmitted over long distances because:

$A$ wave with a wavelength of $0.60 \ cm$ is produced in air and it travels at a speed of $300 \ ms^{-1}$. This wave is classified as:

The figure represents the instantaneous picture of a longitudinal harmonic wave travelling along the negative $x$-axis. Identify the correct statement$(s)$ related to the movement of the points shown in the figure. The points of maximum rarefaction are

The Earth has a radius of $6400 \ km$. The inner core of $1000 \ km$ radius is solid. Outside it,there is a region from $1000 \ km$ to a radius of $3500 \ km$ which is in a molten state. Then again from $3500 \ km$ to $6400 \ km$,the Earth is solid. Only longitudinal $(P)$ waves can travel inside a liquid. Assume that the $P$ wave has a speed of $8 \ kms^{-1}$ in solid parts and of $5 \ kms^{-1}$ in liquid parts of the Earth. An earthquake occurs at some place close to the surface of the Earth. Calculate the time after which it will be recorded in a seismometer at a diametrically opposite point on the Earth if the wave travels along the diameter.

$A$ man sets his watch by a whistle that is $2\, km$ away. How much will his watch be in error? (Speed of sound in air = $330\, m/s$)

The ratio of the velocity of sound in hydrogen $\left(\gamma=\frac{7}{5}\right)$ to that in helium $\left(\gamma=\frac{5}{3}\right)$ at the same temperature is