The velocity at which the flow changes from the laminar flow to the turbulent flow, is called critical velocity. It is of two types, i.e., lower critical velocity and higher critical velocity.
The velocity at which the laminar flow stops, is known as lower critical velocity, while the velocity at which the turbulent flow starts, is known as higher critical velocity.
101) The velocity corresponding to Reynold number of 2000 is called
Answer is:
lower critical velocity
Explanation:
Related Hydraulics and fluid mechanics MCQ with Answers
Answer is:
9.81 kN/m3
Explanation:
Weight density or specific weight is defined as the weight per unit volume of a liquid at a standard temperature and pressure. Weight density or specific weight is usually denoted by w. Weight density or specific weight is expressed in kN/m3 or N/m3 or N/mm3.
Mathematically, weight density or specific weight,
w = ρ.g
Note: For water, w = 9.81 kN/m3 = 9.81 x 103 N/m3 = 9.81 x 10-6N/mm3.
Answer is:
one-third of the total supply head
Answer is:
Weber's number is the ratio of inertia force to surface tension force.
Explanation:
The important dimensionless numbers in fluid mechanics are
1. Reynold’s number
2. Froude’s number
3. Weber’s number
4. Euler’s number
5. Mach’s number or Cauchy’s number
Reynold’s number: Reynold’s number is the ratio of inertia force to the viscous force.
Froude’s number: Froude’s number is the ratio of inertia force to the gravity force.
Weber’s number: Weber’s number is the ratio of inertia force to the surface tension force.
Euler’s number: Euler’s number is the ratio of inertia force to the pressure force.
Mach’s number or Cauchy’s number: Mach’s number or Cauchy’s number is the ratio of inertia force to the elastic force.