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प्रश्न
During propagation of a plane progressive mechanical wave ______.
- all the particles are vibrating in the same phase.
- amplitude of all the particles is equal.
- particles of the medium executes S.H.M.
- wave velocity depends upon the nature of the medium.
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उत्तर
b, c and d
Explanation:
During the propagation of a plane progressive mechanical wave, as shown in the diagram, the amplitude of all the particles is equal.
a. Clearly, the particles O, A and B are having different phases.
b. Particles of the wave shown in the figure are having up and down SHM.
c. For a progressive wave propagating in a fluid.
Speed = v = `sqrt(B/ρ)`
Hence, `v ∝ sqrt(1/ρ)` ......[∵ B is constant]
d. As ρ depends upon the nature of the medium, hence v also depends upon the nature of the medium.
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