CBSE
Multiple Choice QuestionsA point source emits sound equally in all directions in a non-absorbing medium. Two points P and Q are at distance of 2m and 3m respectively from the source. The ratio of the intensities of the waves at P and Q is
9:4
2:3
3:2
4:9
The time of reverberation of a room A is one second. What will be the time (in seconds) of reverberation of a room, having all the dimensions double of those of room A?
2
4
1
An observer moves towards a stationary source of sound, with a velocity one-fifth of the velocity of sound. What is the percentage increase in the apparent frequency ?
Zero
0.5 %
5 %
20 %
Two vibrating tuning forks produce progressive waves given by y1 = 4 sin 500 πt and y2 = 2 sin 506 Πt. Number of beats produced per minute is
360
180
3
60
A closed argon pipe and an open argon pipe are tuned to the same fundamental frequency. What is the ratio of their lengths?
1:2
2:1
2:3
4:3
A person is observing two trains one coming towards him and other leaving with the same
velocity 4 m/s. If their whistling frequencies are 240 Hz each, then the number of beats per second heard by the person will be : ( if velocity of sound 320 m/s)
3
6
9
zero
A particle is executing two different simple harmonic motions, mutually perpendicular, of different amplitudes and having phase difference of The path of the particle will be
circular
straight line
parabolic
elliptical
A particle is executing the motion x = αcos(ωt-θ).The velocity of the particle is
αω cosθ
αω
αω sinθ
None of the above
There are 26 tuning forks arranged in the decreasing order of their frequencies. Each tuning fork gives 3 beats with the next. The first one is octave of the last. What is the frequency of 18th tuning fork?
100 Hz
99 Hz
96 Hz
103 Hz
Which one of the following statements is true?
Both light and sound waves in air are transverse
The sound waves in air are longitudinal while the light waves are transverse
Both light and sound waves in air are longitudinal
Both light and sound waves can travel in vacuum
