CBSE
A stationary source emits a sound moving towards a wall with a velocity u. Speed of sound in air is v. The fractional change in the wavelength of the sound sent and the reflected sound is
Two tunning forks A and B, produce notes of frequencies 258 Hz and 262 Hz. An unknown note sounded with A produces certain beats. When the same note is sounded with B. The beat frequency gets doubled. The unknown frequency is
250 Hz
252 Hz
254 Hz
256 Hz
The equation of a simple harmonic wave is given by y = 3sin (50 t - x) where, x and y are in meters and t in seconds. The ratio of maximum particle velocity to the wave velocity is
2
The equation of a wave is y = 5 sin where x is in cm and t in seconds. The maximum velocity of the wave will be
1 ms-1
2 ms-1
1.5 ms-1
1.25 ms-1
The displacement y of a particle in a medium can be expressed as y =10-6 sin (l00t + 20x + / 4) m, where t is in second and x in metre. The speed of the wave is
2000 m/s
5 m/s
20 m/s
5 m/s
Two sound waves with wavelengths 4 m and 5 m respectively each propagating in a gas with velocity 340 m/s. The number of beats per second will be
12 Hz
15 Hz
17 Hz
11 Hz
Two strings with mass per unit length of 9 gcm-1 and 25 gcm-1 are joined together in series. The reflection coefficient for the vibration waves are
If the phase difference between two points is 60° on a wave velocity of 360 m/s and frequency 500 Hz, then path difference between the two points is
1 cm
6 cm
12 cm
24 cm
A bat emitting an ultrasonic wave of frequency 2 x 104 Hz flies at a speed of 6 m/s between two parallel walls. The beat frequency between the two frequencies heard
by the bat is (Given, speed of sound is 330 m/s)
600 Hz
800 Hz
900 Hz
1300 Hz
In a wave motion y = A sin (kx - ωt), y can represent
electric field
magnetic field
displacement
pressure