Waves - NEET Physics Questions
Question 1: moderate

In a gaseous medium on increasing temperature 800 K, speed of sound becomes √5 times of initial then initial temperature of medium in °C is

1. 27Β°C
2. 300 Β°C
3. - 73Β°C
4. 73Β°C
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Question 2: easy

Velocity of sound in medium is V. If the density of the medium is doubled, what will be the new velocity of sound ?

1. √2 V
2. V
3. 4V
4. V/√2
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Question 3: moderate

For sound waves propagating in a medium, identify the property that is independent of the others :

1. Velocity
2. Wavelength
3. Frequency
4. All these depend on each other
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Speed of sound wave depends on medium and is independent of wavelength and frequency.

Question 4: easy

Speed of sound waves in a fluid depends upon

1. Directly on density of the medium
2. Square of Bulk modulus of the medium
3. Directly on the square root of density
4. Directly on the square root of bulk modulus of the medium
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Speed of sound in a fluid is given by

\[ v = \sqrt{\frac{B}{\rho}} \]

Question 5: moderate

Two waves of amplitude 2A and A of same frequency and velocity propogate in same direction with same phase. Then resultant amplitude is

1. 3A
2. √5A
3. √2A
4. A
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Resultant amplitude

\[ R= \sqrt{A^{2}+(2A)^{2}+ 2A.2A cos\theta} \]

As ΞΈ = 0ΒΊ

R= A+2A=3A

Question 6: moderate

Two waves of intensity I1 and I2 propagate in a medium in same direction. Then sum of maximum and minimum intensity is

1. \[ \left( \sqrt{I_{1}} -\sqrt{I_{2}}\right)^{2}\]
2. \[2 (I_{1}+I_{2}) \]
3. \[ (I_{1}+I_{2}) \]
4. \[ \left( \sqrt{I_{1}} +\sqrt{I_{2}}\right)^{2}\]
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\[ I _{max= }\left( \sqrt{I_{1}} +\sqrt{I_{2}}\right)^{2} \]

\[ I _{min = }\left( \sqrt{I_{1}} - \sqrt{I_{2}}\right)^{2} \]

\[ I _{max} + I _{min} = 2(I_{1} + I_{2})\]

Question 7: easy

Two waves of intensity ratio 9 : 1 produce interference then

\[ \frac{I _{max}}{I _{min} } = \]

1. 2:1
2. 4:1
3. 9:1
4. 10:8
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Question 8: easy

In a stationary wave all the particles

1. On either side of a node vibrate in same phase
2. In the region between two nodes vibrate in same phase
3. In the region between two antinodes vibrate in same phase
4. Of the medium vibrate in same phase
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Question 9: easy

The particle displacement (in cm) in a stationary wave is given by y(x, t) = 2 sin (0.1 Ο€x) cos (100 Ο€t). The distance between a node and the next antinode is

1. 2.5 cm
2. 7.5 cm
3. 5 cm
4. 10 cm
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Question 10: difficult

Two wires are kept tight between the same pair of support. The tensions in the wires are in the ratio 2 : 1, the radii are in the ratio 3 : 1 and the densities are in the ratio 1 : 2. The ratio of their fundamental frequencies is

1. 2 : 3
2. 2 : 4
3. 2 : 5
4. 2 : 6
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