281. An ideal fluid is
A.Similar to perfect gas
B.One which obeys Newton's law of viscosity
C.Frictionless and incompressible
D.Very viscous

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282. If a mouthpiece is running full at the outlet, the vacuum created at vena-contracta
A.Increases velocity of jet
B.Decreases velocity of jet
C.Decreases the discharge
D.Decreases the value of coefficient of contraction

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283. Vertical distribution of velocity in an open channel for laminar flow can be assumed as
A.Logarithmic
B.Parabolic
C.Straight line (constant)
D.Hyperbolic

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284. Vertical distribution of velocity in an open channel for turbulent flow can be assumed as
A.Logarithmic
B.Parabolic
C.Straight line (constant)
D.Hyperbolic

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285. The most economical channel section is one for which the following parameter is maximum for a given, cross sectional area
A.Velocity
B.Discharge
C.Depth
D.Wetted perimeter

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286. The most economical section of a rectangular channel for maximum discharge is obtained when its depth is equal to
A.Half the breadth
B.Twice the breadth
C.Same as the breadth
D.3th the breadth 4

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287. One dimensional flow is
A.Restricted to flow in a straight line
B.Uniform flow
C.One which neglects changes in a transverse direction
D.The most general flow

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