Question

1)What does the conservation of energy state?

2)What are Sir Newton’s three laws of motion?

3)What are the differences between a liquid and a gas?

4)What are the different types of flow? Describe each type of flow?

5)What is Pascal’s Law?

6)What principle does a pump operate on?

7)What are the two board categories of pumps? Describe each.

8)Name three types of directional control valves and describe each.

9)What is pump cavitation? What rules should be followed to prevent/eliminate cavitation?

10)Differentiate between energy and power.

Answer 1

1)

Law of Conservation of Energy

The conservation of energy states that Energy neither be created nor destroyed. but only changed from one form into another or transferred from one object to another.

2)

• Newton's First Law of Motion : Inertia

An object will remain at rest or will continue to move uniformly in a stright line at a constant velocity (speed and direction) unless acted upon by a force

• Newton's Second Law of Motion: Acceleration

The rate of change of velocity of an object is proportional to the force acting on it.

• Newton's Third Law of Motion : Action and Reaction

If one objects exerts a force on another, that second object exerts an equal and opposite force on first.

3)

LIQUIDS	GAS
In liquid phase the atoms are somewhat closely packed	In gas phase the atoms are very loosely packed
Liquids cannot be compressed	gas can be compressed.
Liquids flow from higher level to lower level	gases flow in random direction
The molecular movement results in liquids having a definite and fixed volume	Due to their molecular structure, gases do not have a definite volume

4)Types Of Fluid Flow:-

1) Steady & Unsteady Flows.

Steady Flows:- In which the fluid Characteristics Like velocity, pressure, density , etc. At a Point do not change with time.

Unsteady Flow:- In which the fluid velocity , pressure or density at a point changes with respect to time.

2) Uniform & Non-uniform Flows.

Uniform Flow:- In which the velocity at given time does not change with respect to space ( length of direction of the flow )

Non-Uniform Flow:- In which the velocity at any time changes with respect to space. Changing in space

3) Laminar & Turbulent Flows.

Laminar Flow:- in which the fluid particles move along well defined paths or stream line

Turbulent Flow:- fluid moves in very irregular paths or zig – zag Way. velocity at a point fluctuates

4) Compressible & Incompressible Flows.

Compressible Flows:- In which the density of the fluid changes from point to point. The density is not constant for the fluid.

Incompressible Flows:- In which the density of fluid changes from point to point. the density is constant for the fluid

5) Rotational

In which the fluid particles while flowing along stream lines, Also rotate about their own axis.

& Irrotational Flows.

In which the fluid particles while flowing along stream lines, do not rotate about their own axis.

6) One dimensional flow

In which the flow parameter such as velocity is a function of time and one space co-ordinate only.

Two Dimensional Flow

In which the velocity is a function of time and two rectangular space co-ordinates.

& Three Dimensional Flows.

In which the velocity is the function of time and Three mutually perpendicular directions.

5)

Pascal's law state that pressure at any point in a body of fluid is the same in every direction, exerting equal force on equal areas.