A tuning fork A produces 4 beats/s with another tuning fork B of frequency 320 Hz. On filing one of the prongs of A, 4 beat/s are again heard when sounded with the same fork B . Then, the frequency of the fork A before filing is
328 Hz.
316 Hz.
324 Hz.
320 Hz.
A motor cycle starts from rest and accelerates along a straight path at 2 m/s2. At the starting point of the motor cycle there is a stationary electric siren. How far has the motor cycle gone when the driver hears the frequency of the siren at 94% of its value when the motor cycle was at rest ? (Speed of sound = 330 ms-1).
49 m
98 m
147 m
196 m
The waves, in which the particles of the medium vibrate in a direction perpendicular to the direction of wave motion, is known as.
Transverse waves
Longitudinal waves
Propagated waves
None of these
The frequency of tuning fork is 256. It will not resonate with a fork of frequency
256
512
738
768
The second overtone of an open pipe has the same frequency as the first overtone of a closed pipe 2 m long. The length of the open pipe is
8 m
4 m
2 m
1 m
An organ pipe open at one end is vibrating in first overtone and is in resonance with another pipe open at both ends and vibrating in third harmonic. The ratio of length of two pipes is.
1:2
4:1
8;3
3:8
The plane wave is described by the equation
30 ms-1
40 ms-1
A standing wave is represented by y = asin (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
When the source is moving towards the stationary observer, the apparent frequency is given by
The speed of sound in oxygen (O2) at a certain temperature is 460 ms-1.The speed of sound in helium (He) at the same temperature will be (assume both gases to be ideal)
460 ms-1
500 ms-1
650 ms-1
1420 ms-1
