A plus of wave train travels along a stretched string and reaches the fixed end of the string. It will be reflected back with:
A phase change of 180° with velocity reversed
The same phase as the incident pulse with no reversal of velocity
A phase change of 180° with no reversal of velocity
The same phase as the incident pulse, but with velocity reversed
The transverse wave represented by the equation will have :
Amplitude = 4π
Speed of propagation = 5
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
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
A wave in a string has an amplitude of 2cm. The wave travels in the +ve direction of x axis with a speed of 128 ms-1 and it is noted that 5 complete waves fit in 4 m length of the string. The equation describing the wave is:
y = (0.02)m sin (7.85 x + 1005t)
y = (0.02)m sin (15.7 x - 2010t)
y = (0.02)m sin (15.7 x + 2010t)
y = (0.02)m sin(7.85 x - 1005t)
Each of the two strings of length 51.6 cm and 49.1 cm are tensioned separately by 20 N force. Mass per unit length of both the strings is same adn equal to 1 gm-1. When both the strings vibrate simultaneously the number of beats is:
5
7
8
3
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
Two periodic waves of intensities I1 and I2 pass through a region at the same time in the same direction. The sum of the maximum and minimum intensities is:
I1 + I2
2(I1 + I2)
Which of the following equation represents a wave?
y = a sin ωt
y = a cos kx
y = a sin (ωt - bx + c)
y = a sin (ωt - kx)
The velocity of sound in any gas depends upon:
Wavelength of sound only
Density and elasticity of gas
Intensity of sound waves only
Amplitude and frequency of sound
