Questions of 9.2
1. What is a hydraulic?
2. What is a hydraulic system?
3. Give some examples of hydraulic system.
4. What is a pneumatic?
5. What is a pneumatic system?
6. Give some examples of pneumatic system.
7. What happened if the hydraulic and pneumatic system loose pressure?
8. List an example on when will people use hydraulic system.
9. What is a fluid system?
10. List a thing that is always used to put the liquid under pressure.
Answers of 9.2
1. The study of how liquids act when they are under pressure.
2. A device that uses pressure to apply a force through a liquid to move something else.
3. Tank, pipe, toothpaste, hose, water pipe.
4. The study of how gases act when they are under pressure.
5. A device that uses pressure to apply a force through a gas to move something else.
6. Filled tires, drill teeth, air brakes, vacuum cleaner.
7. They can not work or may not function well.
8. To turn on a hose or a water tap.
9. Something that makes use of a gas or a liquid to perform tasks.
10. pumps
2008年5月7日 星期三
Questions of 9.1
Questions of 9.1
1. The pressure of air sea level is called __________.
2. The tendency for objects to rise or float in a fluid is called _________.
3. What caused Buoyancy to occur?
4. If the _______ force is greater than the force of _______ the object will rise.
5. For water, air, and all other fluids, pressure ______ with ______.
6. Is the air pressure on the mountain greater or at the base? Why?
7. Which of the following has less dense, cooler air or heated air?
8. Why does pressure in a fluid increase with depth?
9. What will happen if the buoyant force is equal to the force of gravity?
10. Give an example when the buoyant force is greater than the gravity.
Answer key
1. One atmosphere
2. buoyancy
3. Because of differences in density
4. buoyant, gravity
5. increase, depth
6. At the base, because air pressure increase with depth.
7. Heated air
8. There is a lot more water pushing down on the water at the bottom.
9. The object will float.
10. Helium balloon
2008年2月9日 星期六
9.3 Natural Fluid system
circulatory system
The circulatory system is an example of a natural fluid system.
The heart bumps blood through the circulatory system.
The force of the blood on the walls of the blood vessels is called blood pressure.
breathing is partly the result of changes in air pressure.
The circulatory system is an example of a natural fluid system.
The heart bumps blood through the circulatory system.
The force of the blood on the walls of the blood vessels is called blood pressure.
breathing is partly the result of changes in air pressure.
Natural Fluid system
Natural fluid system exist around us in atmosphere.(inside earth, in the oceans)
understanding fluid system also allows us to develop new models for forcasting extreme weather like hurricans.
Fluid systems in human
humans' body is an excellent example of a natural fluid system.
The human body is about 66 percent water.
Water plays many important roles in our body.
Natural fluid system exist around us in atmosphere.(inside earth, in the oceans)
understanding fluid system also allows us to develop new models for forcasting extreme weather like hurricans.
Fluid systems in human
humans' body is an excellent example of a natural fluid system.
The human body is about 66 percent water.
Water plays many important roles in our body.
- absorb food
- transport nutrients
- remove wastes
- protect our tissues
too much or too little water can interfere with proper blood circulation.
The circulatory system
The most efficient natural hydraulic systems is the human circulatory system.
The circulatory system transports blood around the body. Blood vessels are like pipelines that carry the blood to all parts of the body.
At the centre of the circulatory system is the powerful and amazing pump, the heart.
The constanting beating of the heart keeps the blood moving throughout the blood vessels.
Blood pressure
The force of the blood on the walls of the blood vessels is called blood pressure.
Blood pressure is measured with a sphygmomanoter. A sphygmomanoter works by putting pressure on the blood vessels in your arm to stop the flow of blood for a few seconds. The doctor listens carefully with a stethoscope as the pressure of the sphygmomanometer is released.
Blood pressure is measured with a sphygmomanoter. A sphygmomanoter works by putting pressure on the blood vessels in your arm to stop the flow of blood for a few seconds. The doctor listens carefully with a stethoscope as the pressure of the sphygmomanometer is released.
Anything that blocks blood vessels can cause problems for the whole system, such as heart attack. Arteries are blood vessels that carry blood away from the heart. If arteries become blocked, blood pressure can get too high or too low.
The respiratory system and pneumatic system
The respiratory system is the body system that brings air into the body and remove carbon dioxide from the body.
Breathing involves changes in air pressure inside and outside our body.
When you inhale , your chest expands because muscles between your ribs push the ribs apart to make a bigger space.
A sheet of muscle in the lower chest, called the diaphragm, moves downward to make a bigger space.
The bigger space in your chest makes the air pressure inside your lungs lower. The air outside your body is higher in pressure. so the air rushes into your body and into your lungs.
When you exhale, the air pressure inside your lungs gets higher. Air is pushed out of your lungs and out of your body.
Anything that blocks the passages that carry air in and out of your body can cause problems for the whole system.
passages can swell up from infections.
A disease called athama also makes the passages narrower.
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The respiratory system and pneumatic system
The respiratory system is the body system that brings air into the body and remove carbon dioxide from the body.
Breathing involves changes in air pressure inside and outside our body.
When you inhale , your chest expands because muscles between your ribs push the ribs apart to make a bigger space.
A sheet of muscle in the lower chest, called the diaphragm, moves downward to make a bigger space.
The bigger space in your chest makes the air pressure inside your lungs lower. The air outside your body is higher in pressure. so the air rushes into your body and into your lungs.
When you exhale, the air pressure inside your lungs gets higher. Air is pushed out of your lungs and out of your body.
Anything that blocks the passages that carry air in and out of your body can cause problems for the whole system.
passages can swell up from infections.
A disease called athama also makes the passages narrower.
.JPG)
2008年2月7日 星期四
9.2 Constructed fluid system
A Fluid system
A fluid system is something that makes use of a gas or a liquid to perform tasks.
liquid=hydraulic system.
gas=pneumatic system.
ex: the pipes are part if the fluid system.
A jackhammer that chip throuh pavement is also a fluid system.
Hydraulic system
Hydraulics is the study of how liquids act when they are under pressure.
Most hydraulic systems apply a force on a liquid that fills a closed space. ex: tank or a pipe.
You use a hydraulic system when you turn on a hose or water pipe.
#When you squeeze a toothpaste, you are using a hydraulic system, too.
A fluid system is something that makes use of a gas or a liquid to perform tasks.
liquid=hydraulic system.
gas=pneumatic system.
ex: the pipes are part if the fluid system.
A jackhammer that chip throuh pavement is also a fluid system.
Hydraulic system
Hydraulics is the study of how liquids act when they are under pressure.
Most hydraulic systems apply a force on a liquid that fills a closed space. ex: tank or a pipe.You use a hydraulic system when you turn on a hose or water pipe.
#When you squeeze a toothpaste, you are using a hydraulic system, too.
In many hydraulic systems, pumps are used to give the force that pushes the liquid. It puts the liquid under pressure.
Mechanics depend on hydraulic system to lift cars and heavy objects.
They use a hyraulic multiplication to increase and transmit a force through a liquid from one place ot another.
Pneumatic system
Pneumatic is the study of how gasesact when they are under pressure.
Pneumatic system: A device that uses gas under pressure to apply a force in order to move something.
The force of pneumatic system can be used to fill tires, bring heavy trucks to a safe stop-air brakes.
Problems with hydraulic and pneumatic systems
#Hydraulic and pneumatic systems cannot work if they lose pressure.
#Hydraulic and pneumatic systems cannot work if they become blocked.
Ex: if a vacuum cleaner become clogged with dust it will not work well.
Mechanics depend on hydraulic system to lift cars and heavy objects.
They use a hyraulic multiplication to increase and transmit a force through a liquid from one place ot another.
Pneumatic system
Pneumatic is the study of how gasesact when they are under pressure.
Pneumatic system: A device that uses gas under pressure to apply a force in order to move something.
The force of pneumatic system can be used to fill tires, bring heavy trucks to a safe stop-air brakes.
Problems with hydraulic and pneumatic systems
#Hydraulic and pneumatic systems cannot work if they lose pressure.
#Hydraulic and pneumatic systems cannot work if they become blocked.
Ex: if a vacuum cleaner become clogged with dust it will not work well.
9.1 Fluids under pressure
How does pressure in fluids change with depth?
There is very little water pushing down on the water at the top of the tube.
#Lots more water pushing down at the bottom.=pressure at the bottom is higher.
water, air, and other fluids, pressure increases with depth.
The pressure of airat sea levelis called one atmosphere(1 atm).
=101.3Kpa
#with each 10m go deeper in the waterthan sea level, pressure goes up by 1 atm.(1 atm =10000kgpushing down on the area of 1 square meter)
Buoyancy
Buoyancy is the tendency for objects to rise or float in a fluid.
Buoyancy occurs because of differences in densityof the object and the fluid.
Buoyant force: Objects rise or float in a fluid because the fluid pushes up on them with a force.
Convection
The buoyant force us what makes heated air rises.
#The density of the heated air is less then the desity of the cooler air.
so the heated air rises, the cooler air sinks.
This transfer of heat throught the flow of a heated fluid is called convection.
#When the buoyant and the force of gravity are unbalanced, object will move direction to the larger force.
#When the two forces are balanced, no motion will occur.
examples:
There is very little water pushing down on the water at the top of the tube.
#Lots more water pushing down at the bottom.=pressure at the bottom is higher.
water, air, and other fluids, pressure increases with depth.
The pressure of airat sea levelis called one atmosphere(1 atm).
=101.3Kpa
#with each 10m go deeper in the waterthan sea level, pressure goes up by 1 atm.(1 atm =10000kgpushing down on the area of 1 square meter)
Buoyancy
Buoyancy is the tendency for objects to rise or float in a fluid.
Buoyancy occurs because of differences in densityof the object and the fluid.
Buoyant force: Objects rise or float in a fluid because the fluid pushes up on them with a force.
Convection
The buoyant force us what makes heated air rises.
#The density of the heated air is less then the desity of the cooler air.
so the heated air rises, the cooler air sinks.
This transfer of heat throught the flow of a heated fluid is called convection.
#When the buoyant and the force of gravity are unbalanced, object will move direction to the larger force.
#When the two forces are balanced, no motion will occur.
examples:
2008年2月3日 星期日
USEFUL LINK
Bc science 8 :http://www.bcscience.com/bc8/index.html
wikipedia :
http://en.wikipedia.org/wiki/Main_Page
Mr. Fuerderer's blog : http://sfuerderer.blogspot.com/
Brianne's blog : http://www.briannesenior.blogspot.com/
Burnaby South :http://south.sd41.bc.ca/
Burnaby South homework
site :http://learn.sd41.bc.ca/QuickPlace/south_homework/Main.nsf/h_Toc/334051017b8104408825721f00530a84/?OpenDocument
wikipedia :
http://en.wikipedia.org/wiki/Main_Page
Mr. Fuerderer's blog : http://sfuerderer.blogspot.com/
Brianne's blog : http://www.briannesenior.blogspot.com/
Burnaby South :http://south.sd41.bc.ca/
Burnaby South homework
site :http://learn.sd41.bc.ca/QuickPlace/south_homework/Main.nsf/h_Toc/334051017b8104408825721f00530a84/?OpenDocument
Questions of 8.3
Questions
1.A(n) _____is any substance that flows.
2.Explain what is viscosity?
3.what happened when the viscosity of a fluid decrease.
4.How can you compare the viscosity of different fluids?
5.What happens when a gas is heated?
6.The slower the fluid flow, the _____ the viscosity.
7.Heating a liguid ____ its viscosity.
8.Give some example of viscous liquid.
9. What does surface tension means?
10.The ____ of a liquid is the speed at which a fluid flows from one point to another.
Answers
1.fluid
2.The thinness or thickness of a liquid is a property of fluids calles viscosity.
3.When the viscosity of a fluid decrease, its flow rate increase.
4.You can compare the viscosity of different fluids by comparing their flow rate.
5.Heating a gas increase its viscosity.
6.higher.
7.Heating a liquid decreased its viscosity.
8.molasses, oil, honey.
9.The water particles at the surface attract each other in a way that makes the surface act like a skin.
10. flow rate
1.A(n) _____is any substance that flows.
2.Explain what is viscosity?
3.what happened when the viscosity of a fluid decrease.
4.How can you compare the viscosity of different fluids?
5.What happens when a gas is heated?
6.The slower the fluid flow, the _____ the viscosity.
7.Heating a liguid ____ its viscosity.
8.Give some example of viscous liquid.
9. What does surface tension means?
10.The ____ of a liquid is the speed at which a fluid flows from one point to another.
Answers
1.fluid
2.The thinness or thickness of a liquid is a property of fluids calles viscosity.
3.When the viscosity of a fluid decrease, its flow rate increase.
4.You can compare the viscosity of different fluids by comparing their flow rate.
5.Heating a gas increase its viscosity.
6.higher.
7.Heating a liquid decreased its viscosity.
8.molasses, oil, honey.
9.The water particles at the surface attract each other in a way that makes the surface act like a skin.
10. flow rate
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