Beats Questions

Two vibrating tuning forks produce progressive waves given by y1 = 4 sin 500 πt and y 2 = 2 sin 506 πt. Number of beats produced per minute is :

Each of the two strings of length $51.6\text{cm}$ and $49.1\text{cm}$ are tensioned separately by $20\text{N}$ force. Mass per unit length of both the strings is same and equal to $1\text{g/m}$. When both the strings vibrate simultaneously, the number of beats is:

A tuning fork of frequency $512\text{ Hz}$ makes $4\text{ beats per second}$ with the vibrating string of a piano. The beat frequency decreases to $2\text{ beats per sec}$ when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was:

Two wires under tension $T$ have frequency $600\text{Hz}$. Fractional increase in tension of one to produce $6\text{beats/s}$ is:

Two sources of sound placed close to each other, are emitting progressive waves given by $y_1=4\sin 600\pi t$ and $y_2=5\sin 608\pi t$. An observer located near these two sources of sound will hear:

A source of unknown frequency $f_u$ gives $4\text{beats/s}$ with a known source of $250\text{Hz}$. The second harmonic of $f_u$ ($2f_u$) gives $5\text{beats/s}$ with a source of $513\text{Hz}$. The unknown frequency is:

Three sound waves of equal amplitudes have frequencies $(n-1),n,(n+1)$. They superimpose to give beats. The number of beats produced per second will be: