An open pipe is in resonance in its 2nd harmonic with tuning fork of frequency f1. Now it is closed at one end. If the frequency of the tuning fork is increased slowly from f1 , then again a resonance is obtained with a frequency f2. If in this case the pipe vibrates in harmonic, then -
(1) n = 3,
(2) n = 3,
(3) n = 5,
(4) n = 5,
Two loudspeakers L1 and L2 driven by a common oscillator and amplifier, are arranged as shown. The frequency of the oscillator is gradually increased from zero and the detector at D records a series of maxima and minima. If the speed of sound is 330 ms–1 then the frequency at which the first maximum is observed is
(1) 165 Hz
(2) 330 Hz
(3) 496 Hz
(4) 660 Hz
A string of length L and mass M hangs freely from a fixed point. Then the velocity of transverse waves along the string at a distance x from the free end is
1.
2.
3. gL
4. gx
Three waves of equal frequency having amplitudes of 10 μm, 4 μm and 7 μm arrive at a given point with a successive phase difference of . The amplitude of the resulting wave in μm is given by:
1. 7
2. 6
3. 5
4. 4
An organ pipe that is closed at one end has a fundamental frequency of 1500 Hz. The maximum number of overtones generated by this pipe that a normal person can hear is:
1. | 14 | 2. | 13 |
3. | 6 | 4. | 9 |
Two pulses in a stretched string whose centres are initially 8 cm apart are moving towards each other as shown in the figure. The speed of each pulse is 2 cm/s. After 2 seconds, the total energy of the pulses will be
1. Zero
2. Purely kinetic
3. Purely potential
4. Partly kinetic and partly potential
The diagram below shows the propagation of a wave. Which points are in the same phase :
(1) F, G
(2) C and E
(3) B and G
(4) B and F
The correct graph between the frequency n and square root of density (ρ) of wire, keeping its length, radius and tension constant, is :
(1)
(2)
(3)
(4)
If the speed of the wave shown in the figure is 330m/s in the given medium, then the equation of the wave propagating in the positive x-direction will be (all quantities are in M.K.S. units) :
(1)
(2)
(3)
(4)
The displacement-time graphs for two sound waves A and B are shown in the figure, then the ratio of their intensities IA/IB is equal to :
1. 1 : 4
2. 1 : 16
3. 1 : 2
4. 1 : 1