CBSE
A wave travelling in the positive x-direction having displacement along y-direction as 1 m, wavelength 2 m and frequency of Hz is represented by
y = sin (x − 2t)
A progressive wave moving along x-axis is represented by . The wavelength (λ) at which the maximum particle velocity is 3 times the wave velocity is
A/3
2A/(3π)
(2/3) πA
If we study the vibration of a pipe open at both ends, then the following statements is not true
Open end will be anti-node
Odd harmonics of the fundamental frequency will be generated
All harmonics of the fundamental frequency will be generated
Pressure change will be maximum at both ends
A car is moving with a speed of 72 km-h-1 towards a roadside source that emits sound at a frequency of 850 Hz. The car driver listens to the sound while approaching the source and again while moving away from the source after crossing it. If the velocity ofsound is 340 ms-1, the difference of the two frequencies, the driver hears is
50 Hz
85 Hz
100 Hz
150 Hz
A whistle whose air column is open at both ends has a fundamental frequency of 5100 Hz. If the speed of sound in air is 340 ms-1, the length of the whistle, in cm, is
5/3
10/3
5
20/3
A train is moving with a uniform speed of 33 m/s and an observer is approaching the train with the same speed. If the train blows a whistle of frequency 1000 Hz and the velocity of sound is 333 m/s, then the apparent frequency of the sound that the observer hears is
1220 Hz
1099 Hz
1110 hz
1200 Hz
The length of an open organ pipe is twice the length of another closed organ pipe. The fundamental frequency of the open pipe is 100 Hz. The frequency of the third harmonic of the closed pipe is
100 Hz
200 Hz
300 Hz
150 Hz
Sound waves are passing through two routes-one in straight path and the other along a semicircular path of radius r and are again combined into one pipe and superposed as shown in the figure. If the velocity of sound waves in the pipe is v, then frequencies of resultant waves of maximum amplitude will be integral multiples of
A source of unknown frequency gives 4 beats/s when sounded with a source of known frequency 250 Hz. The second harmonic of the source of unknown frequency gives five beats per second when sounded with a source of frequency 513 Hz. The unknown frequency is
254 Hz
246 Hz
240 Hz
260 Hz