A wave in a string has an amplitude of 2 cm. 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 (15.7x -2010t)
y = (0.02)n sin (15.7x + 2010t)
y = (0.02)m sin (7.85x - 1005t)
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 a sound in a tissue is 1.7 km/s. 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 x10-4 m
4 x10-3 m
8 x10-3 m
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
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 standing wave having 3 nodes and 2 antinode is formed between two atoms having a distance 1.21 between them, The wavelength of the standing wave is
Two waves of wavelength 50 cm and 51 cm produce 12 beats. The speed of sound is
306 m/s
331 m/s
340 m/s
360 m/s
A pulse of a 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 1800 with velocity reversed
the same phase as the incident pulse with no reversal of velocity
a phase change of 1800 with no reversal of velocity
the same phase as the incident pulse but with velocity reversed
9 : 4
2 : 3
3 : 2
4 : 9
A transverse wave is represented by the equation
If the amplitude of sound is doubles 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
