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 ..... $m$
$2$
$0.4$
$1$
$0.2$
A source of sound is travelling with a velocity of $40\,km/hour$ towards an observer and emits sound of frequency $2000\,Hz$ . If the velocity of sound is $1220\,km/hour$ , what is the apparent frequency heard by the observer ..... $Hz$
A closed organ pipe has length $L$ , the air in it is vibrating in third overtone with maximum amplitude $'a'$ . The amplitude at distance $\frac {L}{7}$ from closed end of the pipe is
Two waves $Y_1=A_1 \sin \,(\omega t -\beta_1)$ and $Y_2 = A_2 \sin \,(\omega t -\beta_2)$ superimpose to form a resultant wave whose amplitude is
A wave travelling along the $x-$ axis is described by the equation $y\ (x, t )\ =\ 0.005\ cos\ (\alpha x - \beta t )$ . If the wavelength and the time period of the wave in $0.08\ m$ and $2.0\ s$ respectively then $\alpha $ and $\beta $ in appropriate units are
The speed of sound in oxygen $(O_2)$ at a certain temperature is $460\, ms^{-1}$. The speed of sound in helium $(He)$ at the same temperature will be ............. $\mathrm{m/s}$ (assume both gases to be ideal)