EASY
Earn 100

A 100 cm string fixed at both ends produces successive resonance frequency 384 Hz and 288 Hz. Wave speed in string is 24n m s-1. Find the value of n.

Important Questions on Superposition of Waves

MEDIUM
A wire having a linear mass density 9.0×10-4 kg m-1 is stretched between two rigid supports with a tension of 900 N. The wire resonates at a frequency of 500 Hz. The next higher frequency at which the same wire resonates is 550 Hz. The length of the wire is ___________ m.
EASY
The equation of stationary wave on a string clamped at both ends and vibrating in third harmonic is given by y=0.5sin(0.314x)cos(600πt), where x and y are in cm and t in second. The length of the vibrating string is (π=3.14)
HARD
Explain the formation of stationary waves in stretched strings and hence deduce the law of transverse waves in stretched strings.
HARD
Two uniform wires of the same material are vibrating under the same tension. If the first overtone of the first wire is equal to the second overtone of the second wire and radius of the first wire is twice the radius of the second wire then the ratio of the lengths of the first wire to second wire is
EASY
A wire of density 9×103 kg cm3 is stretched between two clamps 1 m apart. The resulting strain in the wire is  4.9 × 104. The lowest frequency of the transverse vibrations in the wire (Young's modulus of wire  Y = 9×1010 Nm2 ), (to the nearest integer),_______
MEDIUM
A spring, fixed at one end, is connected to a steel wire of length L. The other end of the steel wire is connected to an AC source providing a sinusoidal signal of fixed frequency f. This stretches the spring and produces standing waves. The spring stretched by 18 cm produces a standing wave with four antinodes in the steel wire. The stretch of the spring which will produce a standing wave of three antinodes is
EASY
The fundamental frequency of a wire stretched by 2 kg wt is 100 Hz. The weight required to produce its octave will be
MEDIUM
A string of length 1 m and mass 2×105 kg is under tension T. When the string vibrates, two successive harmonics are found to occur at frequencies 750 Hz and 1000 Hz. The value of tension T is _____ newton.
EASY
The length of the string of a musical instrument is 90 cm and has a fundamental frequency of 120 Hz Where should it be pressed to produce fundamental frequency of 180 Hz?
EASY
Two identical wires are vibrating in unison. If the tension in one of the wires is increased by 2%, five beats are produced per second by the two vibrating wires. The initial frequency of each wire is 1.02=1.01
HARD
A wire of length 30 cm, stretched between rigid supports, has its nth  and n+1th harmonics at 400 Hz and 450 Hz, respectively. If tension in the string is 2700 N, its linear mass density is _____ kg m-1.
MEDIUM

When a string is divided into three segments of lengthsl1, l2 and l3  the fundamental frequencies of these three segments are ν1, ν2 and ν3 respectively. The original fundamental frequency ν of the string is 

EASY
A guitar string of length 90 cm vibrates with a fundamental frequency of 120 Hz. The length of the string producing a fundamental of 180 Hz will be _____ cm
MEDIUM
A standing wave is produced on a string fixed at one end and free at other. The length of string must be an _______.
 
MEDIUM
A wire of density 8×103 kg m-3 is stretched between two clamps 0.5 m apart. The extension developed in the wire is 3.2×10-4 m. If Y=8×1010 N m-2, the fundamental frequency of vibration in the wire will be _____ Hz
EASY
A string is stretched between fixed points separated by 75.0 cm. It is observed to have resonant frequencies of 420 Hz and 315 Hz. There are no other resonant frequencier between these two. The lowest resonant frequency for this string is:
MEDIUM
A closed organ pipe has a fundamental frequency of 1.5kHz. The number of overtones that can be distinctly heard by a person with this organ pipe will be (Assume that the highest frequency a person can hear is 20,000Hz).
HARD
The ratio of the fundamental frequencies of two identical strings after one of them was stretched by 2% and the other by 4% is (Assume that the tension is proportional to the elongation)
EASY
Two identical strings X and Z made of same material have tension TX and TZ in then if their fundamental frequencies are 450 Hz and 300 Hz, respectively, then the ratio TX/TZ is :
MEDIUM
Two strings of the same material and same length are given equal tension. If they are vibrating with fundamental frequencies 1600Hz and 900Hz, then the ratio of their respective diameters is