Wave Basics & Properties of Sound

A body sends waves $150$ mm long through medium P and $0.30$ m long in medium Q. If the velocity of wave in medium P is $80$ cm/s, the velocity of wave in medium Q in m/s is

A body sends a wave $150$ mm long through medium P and $0.30$ m long in medium Q. If velocity of the wave in medium P is $80$ cm s$-1$, the velocity of wave in medium Q is

The number of waves counted by an observer on the sea-coast in one minute is 54. If the wavelength of the waves is $5$ m then the velocity of the waves in m/s will be

Sound waves travel at $350$ m/s through a warm air and at $3500$ m/s through brass. Which of the following is correct about the wavelength of a $700$ Hz accoustic wave as it enters brass from warm air?

Waves having a velocity 10m/s, strike a stationary boat near the sea shore. The distance between two consecutive crests of the waves is 40m. After how many second, the consecutive waves strike the boat?

The 'Loudness' and 'Pitch' of sound respectively are the human perception to

Which one of the following statements regarding pitch of sound is 'WRONG'?

(A) Pitch refers to sharpness of sound.

(B) Tone refers to the single frequency of that wave.

(C) High pitch sound need not be louder.

(D) In general male sound is sharper than that of a female.

Out of the following musical instruments which is ' NOT ' a percussion instrument?

The amplitude of a sound wave at a distance $r$ from a point source is $A$. The amplitude at a distance $2r$ from the point source is

A point source is kept at the center of a spherically enclosed detector. If the volume of the detector increased by 8 times, the intensity will

A musical instrument P produces sound waves of frequency 'n' and amplitude 'A'. Another musical instrument Q produces sound waves of frequency n/4. The waves produced by P and Q have equal energies. The amplitude of waves produced by Q will be

An observer on sea-coast counts 45 waves in one minute. If the wavelength of the waves is 7 m, then the velocity of the waves will be

A musical instrument ' P ' produce sound waves of frequency ' $n$ ' and amplitude ' $A$ '. Another musical instrument ' $Q$ ' produces sound waves of frequency ' $\frac{n}{4}$ ' The waves produced by ' P ' and ' $Q$ ' have equal energies. If the amplitude of waves produced by ' P ' is ' $A_p$ ', the amplitude of waves produced by ' $Q$ ' will be

Which of the following statements is NOT true?

Prong of a vibrating tuning fork is in contact with water surface. It produces concentric circular waves on the surface of water. The distance between five consecutive crests is 0.8 m and the velocity of wave on the water surface is $56\text{ m/s}$. The frequency of tuning fork is

Out of the following musical instruments, which is 'NOT' a percussion instrument?

How many times more intense is a 60 dB sound than a 30 dB sound?

A point source is emitting sound waves of intensity $16 \times 10^{-8}\text{ Wm}^{-2}$ at the origin. The difference in intensity (magnitude only) at two points located at distances of $2\text{ m}$ and $4\text{ m}$ from the origin respectively will be _________ $\times 10^{-8}\text{ Wm}^{-2}$.

A musical instrument X produces sound waves of frequency n and amplitude A. Another musical instrument $Y$ produces sound waves of frequency $\frac{n}{3}$. The waves produced by $X$ and $Y$ have equal energies. The amplitude of waves produced by Y will be

A musical instrument ' $P$ ' produces sound waves of frequency ' $n$ ' and amplitude ' $A$ '. Another musical instrument ' $Q$ ' produces sound waves of frequency $\frac{n}{4}$. The waves produced by ' $P$ ' and ' $Q$ ' have equal energies. If the amplitude of waves produced by ' $P$ ' is ' $A_P$ ', the amplitude of waves produced by ' $Q$ ' will be

A sound of frequency $480\text{ Hz}$ is emitted from the stringed instrument. The velocity of sound in air is $320\text{ m/s}$. After completing 180 vibrations, the distance covered by a wave is

A rectangular block of mass '$m$' and crosssectional area A, floats on a liquid of density '$\rho$'. It is given a small vertical displacement from equilibrium, it starts oscillating with frequency '$n$' equal to ( $g =$ acceleration due to gravity)

If a wave gets refracted into a denser medium, then which of the following is true?

Which one of the following statements is true?

Two tuning forks of frequencies $320\text{ Hz}$ and $480\text{ Hz}$ are sounded together to produce sound waves. The velocity of sound in air is $320\text{ ms}^{-1}$. The difference between wavelengths of these waves is nearly

The frequency of a tuning fork is $220\text{ Hz}$ and the velocity of sound in air is $330\text{ m/s}$. When the tuning fork completes 80 vibrations, the distance travelled by the sound wave is

The frequency of a tuning fork is 'n' Hz and velocity of sound in air is 'V' m/s. When the tuning fork completes 'x' vibrations, the distance travelled by the wave is

For a transverse wave travelling along a straight line, the distance between two peaks (crests) is 5 m, while the distance between one crest and one trough is 1.5 m. The possible wavelengths (in m) of the wave are:

Assume that the displacement(s) of air is proportional to the pressure difference ($\Delta$p) created by a sound wave. Displacement (s) further depends on the speed of sound (v), density of air ($\rho$) and the frequency (f). If $\Delta$p ~ 10 Pa, v ~ 300 m/s, $\rho$ ~ 1 kg/m3 and f ~ 1000 Hz, then s will be of the order of (take the multiplicative constant to be 1):

A small speaker delivers 2 W of audio output. At what distance from the speaker will one detect 120 dB intensity sound? [Given reference intensity of sound as 10–12 W/m2 ]

In an experiment to determine the period of a simple pendulum of length 1 m, it is attached to different spherical bobs of radii r1 and r2. The two spherical bobs have uniform mass distribution. If the relative difference in the periods, is found to be 5×10−4 s, the difference in radii, $\vert$ r1 $-$ r2 $\vert$ is best given by:

In a transverse wave the distance between a crest and neighbouring trough at the same instant is 4.0 cm and the distance between a crest and trough at the same place is 1.0 cm. The next crest appears at the same place after a time interval of 0.4 s. The maximum speed of the vibrating particles in the medium is:

Sound waves travel at 350 m/s through a warm air and at 3500 m/s through brass. The wavelength of a 700 Hz acoustic wave as it enters brass from warm air

A point performs simple harmonic oscillation of period T and the equation of motion is given by x = a sin($\omega$t + $\pi$/6). After the elapse of what fraction of the time period the velocity of the point will be equal to half of its maximum velocity?

A sound absorber attenuates the sound level by $20\text{ dB}$. The intensity decreases by a factor of

Which one of the following statements is true?

The time of reverberation of a room A is one second. What will be the time (in seconds of reverberation of a room, having all the dimensions double of those of room A?

A point source emits sound equally in all directions in a non-absorbing medium. Two points P and Q are at distances of 2 m and 3 m respectively from the source. The ratio of the intensities of the waves at P and Q is

The equations of two waves acting in perpendicular directions are given as

x = $a$cos($\omega$t +$\delta$) and y = $a$cos($\omega$t + $\alpha$), where $\delta = \alpha + \frac{\pi}{2}$, the resultant wave represents

In a sinusoidal wave, the time required for a particular point, to move from maximum displacement to zero displacement is $0.170\text{ s}$. The frequency of the wave is

A hospital uses an ultrasonic scanner to locate tumours in a tissue. The operating frequency of the scanner is $4.2\text{ MHz}$. The speed of sound in a tissue is $1.7\text{ km/s}$. The wavelength of sound in the tissue is close to

With the propogation of a longitudinal wave through a material medium, the quantities transmitted in the propogation direction are

If the amplitude of sound is doubled and the frequency reduced to one fourth, the intensity of sound at the same point will be