3 3 physics

The fluid can be charactrized two ways

We have laminar

And streamline

Laminar?

If every particle passes through a particular point and another particle passes through the same points its called a streamline

Diffrent steamlines?e.x of streamlines?

Streamlines?

Never intersect one another

The smooth stretches of rivers are examples of laminar flow

Streamlines are in the same direction of the velocity direction vector

The fluid becomes irregular if?

Examples?

They become turbulent when its above a certain velocity or under conditions that can cause changes in velocity

Sharp rocks in the river cause the arubtionof the water

What are regular currents called and what sre irregular currents called?

Regulars are called streamlines irregular are called eddy currents

Where are turbulents found in?

Another difference between them?

Wake of a ship or air currents of a thunder storms

Laminars are predictable but turbulents are unpredictable

many features of liquids can be understood by considering the behaviour of?

Viscosity refers to?

Ideal fluids

When its density allways remains constant

The amount of internal frictionn within a fluid

When can viscosity ocure or internal friction?

Example if the fluid has a high viscosity or low viscosity going through a tube?

When two water lines move past one another

High viscoisity it will go way slower into the pipe

As a viscou fluid flows?

Part of the kinetic energy is transformed into internal energy due to internal friction

But ideal fluids?

Are considered non biscouse so its loses no kinetic energy due to internal friction

Charastristic of ideal fluids?

1They are nonviscouse

2They have a steady flow of

3In other words the velocity density and pressure are constant at each point of the fluid

4The flow is non turbulent which means there are no eddy currents

The ideal flud is only usefull for?

The continuity equation resaulta from

How does the speed of fluid flow change when it goes thorugh a pipe that has different ends

So that means mass 1 is allways equal to mass 2

Analysis

Mass conservation

So we know mass is conserved and we know that liquid is incompressible which causes in the increase of movement

M1=M2

For an ideal fluid both are the same?

So the continuinity equation is?

Time intervall and densities are the same

A1 x V1 = A2 x V2

The speed of fluid flow depends on?

If the pipe is narrow or wide?

The cross sectional area

If its narror it will be faster if its wide it will be slower

Av which has a unit of?

Which is called?

How is the flow rate?

Change in volume per a change in time

The flow rate

Its constant throughout the pipe

An example of

The continiuty equation resualts from mass conservation

When you are watering the plants and use your finger tip

And when the water goes through narrow areas

Relation between pressure in a fluid and speed flow

Is the pressure decreases the velocity increases

Miss toled you to?

There is a net upward force on the wing called?

A plane wing is dessigned to?

Allways use the narrow spot as a1 v1

Lift

Put more pressure on buttom of the wing rather than ontop the wing

Benoulis equation

Why is KE density times velocity ²?

Relates pressure to energy in a moving liquid

Beacuse its energy per a unit volume not just energy E/V

We have two special cases

1 if its static and not mocing which makes the two speeds zero

And beacuse its not moving the h1 is defined zero

2 if the pipe is horizantek pipe then the two Hs are zero

Benoulis principle is strictly true when?

Only when elavation is constant

When the pressure and area increases what happens to the velocity? What about density?

It decreases

It remains constant