If the amplitude of sound is doubled and the frequency reduced to one-fourth, the intensity of sound at the same point will
increase by a factor of 2
decrease by a factor of 2
decrease by a factor of 4
remains unchanged
Two waves of same frequency and intensity superimpose on each other in opposite phases. After the superposition, the intensity and frequency of waves will
increase
decrease
remain constant
become zero
A stretched string resonates with tuning fork frequency 512 Hz when length of the string is 0.5 m. The length of the string required to vibrate resonantly with a tuning fork of frequency 256 Hz would be
0.25 m
0.5 m
1 m
2 m
Equation of progressive wave is given by
Then which of the following is correct?
v = 5 cm
λ = 18 cm
a = 0.04 cm
ƒ = 50 Hz
Velocity of sound waves in air is 330 m/s. For a particular sound wave in air, path difference of 40 cm is equivalent to phase difference of 1.6 π. The frequency of this wave is
165 Hz
150 Hz
660 Hz
330 Hz
Two trains move towards each other with the same speed. The speed of sound is 340 m/s. If the height of the tone of the whistle of one of them heard on the other changes times, then the speed of each train should be
20 m/s
2 m/s
200 m/s
2000 m/s
The speed of a wave in a medium is 760 m/s. If 3600 waves are passing through a point in the medium in 2 min, then their wavelength is
13.8 m
25.3 m
41.5 m
57.2 m
A standing wave is represented by y = a sin (100t) cos(0.01)x, where y and a are in millimetre, t in second and x is in metre. Velocity of wave is
104 m/s
1 m/s
10-4 m/s
Not derivable from above data
Two waves are said to be coherent, if they have
same phase but different amplitude
same frequency but different amplitude
same frequency, phase and amplitude
different frequency, phase and amplitude
A wave of frequency 100 Hz is sent along a string towards a fixed end. When this wave travels back after reflection, a node is formed at a distance of 10 cm from the fixed end of the string. The speed of incident ( and reflected) wave are
5 m/s
10 m/s
40 m/s