NEET UG 2013 — Waves & Oscillations

A source of unknown frequency gives 4 beats/s when sounded with a source of known frequency $250 \mathrm{~Hz}$. The second harmonic of the source of unknown frequency gives five beats per second when sounded with a source of frequency $513 \mathrm{~Hz}$. The unknown frequency is

Two source $\mathrm{P}$ and $\mathrm{Q}$ produce notes of frequency $660 \mathrm{~Hz}$ each. A listener moves from $\mathrm{P}$ to $\mathrm{Q}$ with a speed of $1 \mathrm{~ms}^{-1}$. If the speed of sound is $330 \mathrm{~m} / \mathrm{s}$, then the number of beats heard by the listener per second will be:

The length of the wire between two ends of sonometer is $100 \mathrm{~cm}$. What should be the positions of two bridges below the wire so that the three segments of the wire have their fundamental frequencies in the ratio $1: 3: 5$.

A wave travelling in the positive $x$-direction having displacement along $y$-direction as $1 \mathrm{~m}$, wavelength $2 \pi \mathrm{m}$ and frequency of $\frac{1}{\pi} \mathrm{Hz}$ is represented by

A particle of mass $m$ oscillates along $x$-axis according to equation $x=a$ sin $\omega t$. The nature of the graph between momentum and displacement of the particle is:

If we study the vibration of a pipe open at both ends, then the following statements is not true