A transverse harmonic wave on a string is described by $y = 3\sin \left( {36t + 0.018x + \frac{\pi }{4}} \right)$ where $x$ and $y$ are in $cm$ and $t$ in $s$. The least distance between two successive crests in the wave is .... $m$

Fundamental frequency of a sonometer wire is $n$. If the length and diameter of the wire are doubled keeping the tension same, then the new fundamental frequency is

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

In a sinusoidal wave, the time required for a particular point to move from maximum displacement to zero displacement is $0.170 \,s$. The frequency of wave is ........ $Hz$

A heavy rope is suspended from a rigid support. A transverse wave pulse is set up at the lower end, then

A car sounding its horn at $480\,Hz$ moves towards a high wall at a speed of $20\,m/s$. If the speed of sound is $340\,m/s,$ the frequency of the reflected sound heard by the passenger sitting in the car will be the nearest to ..... $Hz$