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प्रश्न
With propagation of longitudinal waves through a medium, the quantity transmitted is ______.
विकल्प
matter.
energy.
energy and matter.
energy, matter and momentum.
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उत्तर
With propagation of longitudinal waves through a medium, the quantity transmitted is energy.
Explanation:
A wave is a disturbance which propagates energy and momentum from one place to the other without the transport of matter. The propagation of longitudinal waves through a medium leads to the transmission of energy through the medium without the matter being transmitted. There is no movement of matter (mass) and hence momentum.
Important point:
Characteristics of wave motion:
- It is a sort of disturbance which travels through a medium.
- Material medium is essential for the propagation of mechanical waves.
- When a wave motion passes through a medium, particles of the medium only vibrate simply harmonically about their mean position. They do leave their position and move with the disturbance.
- There is a continuous phase difference amongst successive particles of the medium, i.e. particle 2 starts vibrating slightly later than particle 1 and so on.
- The velocity of the particle during their vibration is different at different positions.
- The velocity of wave motion through a particular medium is constant. It depends only on die nature of the medium not on the frequency, wavelength or intensity,
- Energy is, propagated along with the wave motion without any net transport of the medium.
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For the propagation of longitudinal waves, the medium must have
- elasticity
- mass
- inertia
- force of cohesion
