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
20 m/s
40 m/s
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
With the propagation of a longitudinal wave through a material medium, the quantities transmitted in the propagation direction are
energy, momentum and mass
energy
energy and mass
energy and linear momentum
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
For production of beats the two sources must have
different frequencies and same amplitude
different frequencies
different frequencies, same amplitude and same phase
different frequencies and same phase
A hospital uses an ultrasonic scanner to locate tumours in a tissue. The operating frequency of the scanner is 4.2 MHz. The speed of sound in a tissue is 1.7 km/s. The wavelength of sound in tissue is close to
4 x 10-4 m
8 x 10-4 m
4 x 10-3 m
8 x 10-3 m
The frequency of sinusoidal wave, 0.40 cos (2000t + 0.80) would be
1000π Hz
2000 Hz
20 Hz
From a wave equation
the frequency of the wave is
5 Hz
15 Hz
25 Hz
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
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