381. The power transmitted through a pipe is (where w = Specific weight in N/m3, and Q = Discharge in m3/s)
[A]. w x Q x H
[B]. w x Q x hf
[C]. w x Q (H – hf)
[D]. w x Q (H + hf)
✅ The correct answer is option C.
Hydraulics and Fluid Mechanics MCQs
382. The centre of gravity of the volume of the liquid displaced is called
[A]. centre of pressure
[B]. centre of buoyancy
[C]. metacentre
[D]. none of these
✅ The correct answer is option B.
383. In a free nappe,
[A]. the pressure below the nappe is atmospheric
[B]. the pressure below the nappe is negative
[C]. the pressure above the nappe is atmospheric
[D]. the pressure above the nappe is negative
✅ The correct answer is option A.
384. In an external mouthpiece, the absolute pressure head at vena contracta is __________ the atmospheric pressure head by an amount equal to 0.89 times the height of the liquid, above the vena contracta.
[A]. less than
[B]. more than
null
null
✅ The correct answer is option A.
385. The loss of head due to friction in a pipe of uniform diameter in which a viscous flow is taking place, is (where RN = Reynold number)
[A]. 1/RN
[B]. 4/RN
[C]. 16/RN
[D]. 64/RN
✅ The correct answer is option C.
386. When a tube of smaller diameter is dipped in water, the water rises in the tube due to viscosity of water.
[A]. True
[B]. False
null
null
✅ The correct answer is option B.
387. The maximum efficiency of transmission through a pipe is
[A]. 50%
[B]. 56.7%
[C]. 66.67%
[D]. 76.66%
✅ The correct answer is option C.
388. The discharge through a large rectangular orifice is given by (where H1 = Height of the liquid above the top of the orifice, H2 = Height of the liquid above the bottom of the orifice, b = Breadth of the orifice, and Cd = Coefficient of discharge)
[A]. Q = Cd x b2g(H2 – H1)
[B]. Q = Cd x b2g(H21/2 – H11/2)
[C]. Q = Cd x b2g(H23/2 – H13/2)
[D]. Q = Cd x b2g(H22 – H12)
✅ The correct answer is option C.
389. The Bernoulli’s equation is based on the assumption that
[A]. there is no loss of energy of the liquid flowing
[B]. the velocity of flow is uniform across any cross-section of the pipe
[C]. no force except gravity acts on the fluid
[D]. all of the above
✅ The correct answer is option D.
390. A siphon is used to connect two reservoirs at different levels intervened by a high ridge.
[A]. True
[B]. False
null
null
✅ The correct answer is option A.