Hydraulics and Fluid Machanics

1
The depth of centre of pressure lor an immersed surface inclined at an angle `theta` with the liquid surface lies at a distance equal to __________ the centre of gravity.
A. `(l_(Gsin^2 theta))/(A overline(X))`below
B. `(l_(Gsin^2 theta))/(A overline(X))`above
C. `(l_(Gsin theta))/(A overline(X))`below
D. `(l_(Gsin theta))/(A overline(X))`above

2

In order to avoid tendency of separation at throat in a venturimeter, the ratio of the diameter at throat to the diameter of pipe should be

A. `1/16` to `1/8`
B. `1/8` to `1/4`
C. `1/4` to `1/3`
D. `1/3` to` 1/2`

3
The error in discharge (dQ/Q) to the error in measurement of head (dH/H) over a triangular notch is given by
A. `(dQ)/(Q) = 3/2 xx (dH)/(H)`
B. `(dQ)/(Q) = 2 xx (dH)/(H)`
C. `(dQ)/(Q) = 5/2 xx (dH)/(H)`
D. `3 xx (dH)/(H)`

4
According to Darcy's formula, the loss of head due to friction in the pipe is (where f = Darcy's coefficient, l = Length of pipe, v = Velocity of liquid in pipe, and d = Diameter of pipe)
A. `(flV^2)/(2gd)`
B. `(flV^2)/(gd)`
C. `(3flV^2)/(2gd)`
D. `(4flV^2)/(2gd)`

5
The centre of pressure for a vertically immersed surface lies at a distance equal to __________ the centre of gravity.
A. `(l_G)/(A overline(X)`below
B. `(l_G)/(A overline(X)`above
C. `(A overline(X))/(l_G)`below
D. `(A overline(X))/(l_G)`above