The equation of a stationary wave is

$y = 0.8\,\cos \,\,\left( {\frac{{\pi x}}{{20}}} \right)\,\sin \,200\,\pi t$

where $x$ is in $cm$ and $t$ is in $sec$ . The separtion between consecutive nodes will be .... $cm$

The length of open organ pipe is $L$ and fundamental frequency is $f$. Now it is immersed into water upto half of its length now the frequency of organ pipe will be

Beats are produced by two waves $y_1 = a\, sin\, (1000\, \pi t)$ and $y^2 = a\, sin\, (998\, \pi t)$ The number of beats heard per second is

A stretched string is divided into three segments of lengths $50\,cm,\,\,40\,cm$ and $10\,cm$ with the help of bridges. Their vibrations will have frequencies in the ratio

For a certain organ pipe three successive resonance frequencies are observed at $425\, Hz,595 \,Hz$ and $765 \,Hz$ respectively. If the speed of sound in air is $340 \,m/s$,  then the length of the pipe is ..... $m$

A small source of sound moves on a circle as shown in the figure and an observer is standing on $O.$ Let $n_1,\, n_2$ and $n_3$ be the frequencies heard when the source is at $A, B$ and $C$ respectively. Then