Advertisements
Advertisements
Question
When two waves of almost equal frequencies n1 and n2 reach at a point simultaneously, what is the time interval between successive maxima?
Advertisements
Solution
If two waves of almost equal frequencies interfere, they are producing beats.
Let n1 > n2
Beat frequency `f_"beat"` = n1 – n2
∴ Time periods of beats Tbeats = `1/f_"beat" = 1/(n_1 - n_2)`
This time period will be equal to the time interval between successive maxima.
APPEARS IN
RELATED QUESTIONS
Wavelengths of two notes in the air are`[70/153]^m` and `[70/157]^m`. Each of these notes produces 8 beats per second with a tuning fork of fixed frequency. Find the velocity of sound in the air and frequency of the tuning fork.
Explain why (or how) A violin note and sitar note may have the same frequency, yet we can distinguish between the two notes,
Doppler effect is not applicable when _______.
(A) source and observer are at rest.
(B) there is a relative motion between source and observer.
(C) both are moving in opposite directions.
(D) both are moving in same direction with different velocities
A set of 8 tuning forks is arranged in a series of increasing order of frequencies. Each fork gives 4 beats per second with the next one and the frequency of last fork is twice that of the first. Calculate the frequencies of the first and the last fork.
What are beats?
State any four applications of beats.
When the observer moves towards the stationary source with velocity, 'V1', the apparent frequency of the emitted note is 'F1'. When the observer moves away from the source with velocity 'V1', the apparent frequency is 'F2'. If 'V' is the velocity of sound in air and `"F"_1/"F"_2 = 4` then `"V"/"V"_1 = ?`
A tuning fork 'A' produces 5 beats per second with a tuning fork of frequency 480 Hz. When a little wax is stuck to a prong of fork A, the number of beats heard per second becomes 2. What is the frequency of tuning fork A before the wax is stuck to it?
Two waves of wavelength 2 m and 2.02 m, with the same speed superimpose to produce 2 beats per second. The speed of each wave is ____________.
A set of 25 tuning forks is arranged in order of decreasing frequencies. Each fork produces 3 beats with succeeding one. If the first fork is octave of last, then the frequency of 1st and 15th fork in Hz is ______.
Two tuning forks have frequencies 380 Hz and 384 Hz respectively. When they are sounded together, maximum sound is heard. How long will it take to hear the minimum sound?
A set of 56 tuning forks are arranged in series of increasing frequencies. If each fork gives 4 beats with preceding one and the frequency of the last is twice than than that of first, then frequency of the first fork is ____________.
A pipe closed at one end has a length of 1m and at its open end, 0.25 m long uniform string is vibrating in its third harmonic and resonates with a fundamental frequency of pipe. If the tension in the string is 100 N and the speed of sound is 340 `m/s`, then the mass of the string is near ______
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 ______
`(sqrt(1 . 0.2) ≑ 1 . 0.1)`
Two wires are producing fundamental notes of the same frequency. Change in which of the following factors of one wire will NOT produce beats between them?
A tuning fork A, marked 512 Hz, produces 5 beats per second, where sounded with another unmarked tuning fork B. If B is loaded with wax the number of beats is again 5 per second. What is the frequency of the tuning fork B when not loaded?
Two light waves of intensities 'I1' and 'I2' having same frequency pass through same medium at a time in same direction and interface. The sum of the minimum and maximum intensities is ______.
If beat frequency is 2 Hz, what is the time interval between success waxings?
