Wave on water surface are
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Longitudinal
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Transverse
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Combination of longitudinal and transverse.
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None of these
Reveal answer
Fill a bubble to check yourself
C
Correct answer
Explanation
$Answer:-$ C option
Ocean waves are both longitudinal and transverse. Technically, they're a special category called surface waves.
At the surface of the water (or generally any place two fluids of different densities meet) the force of gravity acts as the "returning" force required for transverse waves to propagate. Gravity wants to level out the surface of the water, so peaks try to flatten and troughs try to fill. This is somewhat similar to the way a guitar string tries to return to a straight line after being plucked.
However there is essentially zero shear strength in water, so pure transverse waves would die out extremely quickly. The trick comes from the fact that the water in an ocean wave does not move with the wave itself -- each bit of water can only give its neighbors a push, not flow. This push increases the local pressure in the water, which allows the wave to become deeper/higher.
If you could see the bulk pressure/motion of the water column below the surface, you would immediately see the fact that the "wave" is mostly a localized upswell caused by an actual submerged longitudinal pressure wave. Or you could say the upswell from the wave causes a submerged longitudinal pressure wave beneath it! Two ways to say the same thing. Dynamic fluid behavior is tricky like that.
At the surface of the water (or generally any place two fluids of different densities meet) the force of gravity acts as the "returning" force required for transverse waves to propagate. Gravity wants to level out the surface of the water, so peaks try to flatten and troughs try to fill. This is somewhat similar to the way a guitar string tries to return to a straight line after being plucked.
However there is essentially zero shear strength in water, so pure transverse waves would die out extremely quickly. The trick comes from the fact that the water in an ocean wave does not move with the wave itself -- each bit of water can only give its neighbors a push, not flow. This push increases the local pressure in the water, which allows the wave to become deeper/higher.
If you could see the bulk pressure/motion of the water column below the surface, you would immediately see the fact that the "wave" is mostly a localized upswell caused by an actual submerged longitudinal pressure wave. Or you could say the upswell from the wave causes a submerged longitudinal pressure wave beneath it! Two ways to say the same thing. Dynamic fluid behavior is tricky like that.