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 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
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
The frequency of sinusoidal wave, 0.40 cos (2000t + 0.80) would be
1000π Hz
2000 Hz
20 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
A 5.5 m length of string has a mass of 0.035 kg. If the tension in the string is 77 N, the speed of a wave on the string is
110 ms-1
165 ms-1
77 ms-1
102 ms-1
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
2 m/s
200 m/s
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
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 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
