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Week 5 - Fluid Technologies

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Book: Week 5 - Fluid Technologies
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Date: Monday, 17 November 2025, 5:41 PM

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Week 5 - Fluid Technologies Part 2

Table of contents

1. Pressure

 
Lesson 17: Pressure

Textbook Readings

ScienceFocus 8
Pages 71, 73-75
or
Science in Action 8
Pages 53, 56-59

Both gasses and liquids are considered fluids but only gasses are compressible. Which means that gasses can be squished into a smaller space but that liquids and solids can not. Liquids transfer pressure .
Background Information
Air Pressure Like everything on earth, the air in our atmosphere is being pulled down by gravity. Air pressure is strongest close to the Earth.
More molecules = more weight = more pressure
Air pressure decreases as you move further away from the Earth, therefore air pressure changes with altitude. If you go for a ride on an airplane or dive in the mountains, you ears "pop" as your body adjusts to the change in pressure.
As air is heated, the molecules move farther apart and the air in the balloon becomes less dense. The balloon floats up in the air.

As air is heated, the molecules move farther apart and the air in the balloon becomes less dense. The balloon floats up in the air.

As the air in the balloon cools. The molecules move closer together and the balloon becomes more dense. The balloon returns to Earth.

 
Barometer
Air pressure is measured using a barometer. A simple barometer consists of a thin glass tube in mercury. As the air pressure
  • pushes down on the mercury in the dish the pressure forces the mercury to rise up the narrow tube.
  • decreases the mercury level in the glass tube goes down.
  • increases the mercury level in the glass tube goes up.

Water Pressure

 

Water pressure also changes as you move downward. As a diver moves deeper in the water the pressure increases because the molecules are packed closer together. Water is not compressible, as shown above, but it is under increasing pressure as the depth increases. Since the pressure is already evenly distributed, because the molecules are already close together, the temperature of the water doesn't increase as its depth increases. Another reason the temperature doesn't increase is because it is further from the source of heat (the sun). There are locations in the ocean, however, that are hotter the lower you travel but that is because those areas are close to a different heat source. These heat sources are vents from cracks in the Earth's crust where magma is closer to the surface of the crust in those locations.


© 2002 Alberta Online Consortium

2. Solubility of Materials in Water

Solubility of Materials in Water

 
Lesson 18: Solubility of Materials in Water

Textbook Readings

ScienceFocus 8
Pages 39-41
or
Science in Action 8
Pages 66-68


 
As you have seen from your readings and previous activities water regulates every part of our lives. In this series of lessons you will investigate how many industries use water (often called the universal solvent) to move and separate materials. Everyday items such as sugar and salt are processed and refined with water. Other important minerals such as potash and even gold need water for their refinement as well.


Background Information
Let's explore how solubility can be used to make our lives better.
The Salt of the Earth
Can you imagine a world without salt? In hot dry climates, being without salt means certain death. Luckily, we don't have that problem here. But can you imagine popcorn with out salt - yuck!

How do we get salt? Where does it come from? And what processes are used to get it to our table? Let's find out.
The basic forms of salt mining are:
  1. rock salt mining
  2. solution salt mining.
Two examples of this process are:



Exercise 5.2: Sugar Processing
 



Technology Time - Scuba Diving

Scuba (self-contained underwater breathing apparatus) diving is a wonderful sport and people of all ages are enjoying the adventure it brings. But like all activities it comes with an element of risk.
Your blood contains many dissolved chemicals, including gasses. When a scuba diver breaths compressed air underwater, a larger quantity of nitrogen is dissolved in the blood streambecause of the increased pressure of the water above her. If the diver swims to the surface to quickly, the nitrogen will turn to bubbles in the blood stream. This is referred to as 'decompression sickness' or the 'bends'. This can be very serious and lead to paralysis. That's why it is very important that people new to the sport take courses from a qualified instructor. If the rules of diving are followed, it can be a safe and enjoyable experience.

Buoyancy Control or Why Not to Fall Up!

One of the skills needed to be a scuba diver is buoyancy control. Fish do it all the time. Many fish have an air bladder in their bodies. If they want to go higher in the water column (closer to the surface) they add more air and they float higher. In the picture on the right, you will notice that the diver appears to be wearing a vest. That vest is used for buoyancy control.
Would you like to know more? Check out these web sites:

Buying Scuba Gear
Training and Safety
Diving British Columbia
Decompression Sickness

As the diver goes deeper, the air in her suit and buoyancy compensator (the vest) is squeezed due to the pressure of the water above her. The diver must add more air from his tank in order to achieve neutral buoyancy. That means that she is neither falling to the bottom or rising to the surface.
When the diver wishes to surface he must swim upward. But with less water over him now, the air in his lungs, suit and buoyancy compensator begins to expand. So now he must release air from his suit and compensator or he will rocket to the surface - and you know what that means. The bends!
If your interested in learning more about diving, check out these sites:

Scuba diving explained


Diving in tropical waters


Online scuba magazine


© 2002 Alberta Online Consortium

3. Viscosity Review

Viscosity Review

 
Lesson 19: Slow as Molasses in January
 

Textbook Readings

ScienceFocus 8
Pages 39 - 41
or
Science in Action 8
Pages 66 - 68

"You're as slow a molasses in January! "

A few lessons ago you learned what that statement means. If you have heard it spoken to you, it was probably by your parents when you didn't want to do something - like clean your room. You learned in the previous lesson that the seasonal temperature changes affect the flow of fluids including molasses.
In this lesson we are going to investigate various technologies that depend on fluids to have fairly specific viscosities. For example, how would you like your ketchup to run like water?

Background Information

Viscosity is an internal property of a fluid that offers resistance to flow. For example, pushing a spoon with a small force moves it easily through a bowl of water, but the same force moves mashed potatoes very slowly. In fact, one of the major differences between styles of mashed potatoes is the viscosity of the starchy mass: some people like their potatoes running and teeming with milk and butter (they are fans of low-viscosity potatoes), while others like their potatoes drier and stickier, so they almost crack rather than flow (these people are devoted to high-viscosity potatoes).

http://www.spacegrant.hawaii.edu/class_acts/ViscosityTe.html

Let's go back for a moment and review the factors that affect viscosity.

1. Viscosity can be defined as the amount of friction or internal resistance a fluid has.
2. If it has a high viscosity it will be thick and flow very slowly.
3. Thin runny fluids are said to have a low viscosity.
4. So what do we know of that affects the viscosity of a fluid? Temperature! That means if a industry can control the temperature of a fluid it can generally control the viscosity of that fluid.

For example, in order easily mold steel it must be heated so that it has a low viscosity and can be poured into molds.
The Alberta Tar Sands


Let's look at an industry where the control of temperature and therefore viscosity of their product allows it to be transported.
The Alberta tar sands is second only to Saudi Arabia for amount of oil reserves and could totally supply the world for many years. But the oil in the sand is very viscous . How do they get it out, transport the bitumen and recover the oil? Checkout the web sites below.

Alberta Oil Sands
(See attached file: Alberta Oil Sands Fact Sheet.pdf)
http://www.oilsands.alberta.ca/FactSheets/The_Facts_Aug2011.pdf 

(See attached file: Oil Sands 101)
http://www.imperialoil.com/Canada-English/operations_sands_glance_101.aspx
 
Experiment Time: Motor Oil



Motor oil is one of the fluids in your vehicle and needs periodic changing. Motor oil comes in many viscosities. Take a trip (with a parent) to a service station or garage and talk to the mechanic for a few minutes. Ask him the following questions, and any others you want to make up.
© 2002 Alberta Online Consortium

4. Fluid Transport

Fluid Transport

 
Lesson 20: Natural Gas

 

No Textbook

Readings

for this lesson


Have you ever wondered where the natural gas that heats your home comes from? Or why most people in the hospital are connected to bags hanging from poles?
In this lesson we are going to examine how liquids are transported from one place to another. First, we will examine how natural gas is transported across Canada. Second, we will look at the technology that is used in hospitals to give ailing people food, water and medicine.


Background Information

Intravenous Delivery

Have you ever watched any of those emergency medicine shows on TV? It seems one of the first things they when a person is really sick or injured is to put in an IV ( intravenous ) line. Why? Let's find out. Here is a list of questions that the interviewer in the video is going to ask the nurse at the hospital. After the video, record the answers in the space provided.


Part 1
Part 2


Exercise 5.4A: Health Care

 


Exercise 5.4B: Natural Gas

 


Use the document below to find the answers to the following questions.
Transportation of natural gas:
© 2002 Alberta Online Consortium

5. Unit 1 Section 4-5 Quiz

You will have two opportunities to write this section quiz. This quiz consists of 10 questions. Use the results from your 1st attempt to help you prepare for your second attempt. Your best score will be taken as your assessment mark. You have 20 minutes to complete this multiple choice quiz.


 Click the icon to go to the quiz.