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The maximum velocity of water occurs along a stream meander,These are the choices A)...

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homer-simpson | Student, Grade 9 | Honors

Posted February 21, 2012 at 5:10 AM via web

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The maximum velocity of water occurs along a stream meander,

These are the choices

A) near the outer bank of the meander
B) in the center, on the surface
C) near the stream's bed
D) in the center, below the surface
E) near the inner bank of the meander

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pacorz | High School Teacher | (Level 3) Educator

Posted February 21, 2012 at 6:47 AM (Answer #1)

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A stream's flow is always fastest near the bank, at the outside of a curve or meander. This is because the water is subject to centrifugal force, which occurs when an object or material moves in a circular path. The water at the outside edge of the curve has a longer path to follow than the water near the inside of the curve, so the water at the outside of the curve flows faster to "keep up" with the rest of the stream. Greater speed means the water also flows with more force; this fact also causes erosion to be greatest at the outside of a curve, so that over time the meanders tend to get wider and curvier, which is why natural streams generally have a lot of bends and turns in them.

Sources:

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najm1947 | Elementary School Teacher | Valedictorian

Posted February 21, 2012 at 1:45 PM (Answer #2)

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Generally it is true what is said above by Pacorz, however, in the experiments and my experience as an engineer, I have seen different results owing to following factors:

1. Reresistance of air on the surface of the stream

2. Resistance of embankments and bottom with water stream

3. Internal resistance of water with adjacent layers of water due to speed variation.

4. Shallowness of the stream near embankments of the stream resulting in higher resistance due to combined effect of 3 above.

The resistance of air is lower than the resistance of embankments and its is observed that the velocity of the stream is highest near the centroid of the steam somewhere between the surface and centroid of the cross-section when stream flows in a straight path. The meander will shift the point towards the outer edge due to centrifugal force.

Hence none of the given 5 options A, B, C, D and E fully provide the correct answer. If the choice is to be made from the given options, I would say it is some what like D but towards the outer bank as given in option A.

It is not surely B, C or E the right answer.

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