A normal human being can listen to sounds with frequency from _________to___________ cycles per sec.

Q. A source of sound of frequency n and a listener approach each other with a velocity equal to $\frac{1}{20}$ of velocity of sound. The apparent frequency heard by the listener is

Q. A sound with frequency is inaudible to human being.

Q. A tuning fork producing sound of frequency $380\text{Hz}$ is moving towards a wall with a velocity of $4{\text{ms}}^{-1}$. The number of beats per second heard by a stationary listener produced due to direct and reflected sounds will be
[speed of sound in air $=340{\text{ms}}^{-1}$]

Q. Two sources A and B are sounding notes of frequency 680 Hz. A listener moves from A to B with a constant velocity u. If the speed of sound is 340 m/s, what must be the value of u so that he hears
10 beats per second?

Q. Two sources $A$ and $B$ are sounding notes of frequency $660Hz$ A listener moves from $A$ to $B$ with a constant velocity $u.$ If the speed of sound is $330m/s$ what must be the value of $u$ so that he hears $8$ beats per second?