The beauty of the fluid is its own. The weight of this swimmer is supported by it.

The densities of various substances are compared.

Determine the force given by pressure and area.

Density is given by pressure and altitude.

Understand why objects sink or float.

A breath of fresh winter air; a hot blue flame in our gas cooker; the water we drink, swim in, and bathe in; the blood in our veins are all fluid. The physical characteristics of static or stationary fluids and some of the laws that govern their behavior are the topics of this chapter.

The common phases of matter are a solid, liquid, gas, or plasma. Solids have a definite shape and a specific volume, liquids have a definite volume but their shape changes depending on the container in which they are held, gases have neither a definite shape nor a specific volume as their molecule move to fill the container in which they are held, and plasmas also Solids are considered to be fluids because they resist shearing forces. Poiseuille's Law states that the extent to which fluids yield to shearing forces depends on a quantity called the viscosity. We can understand the phases of matter by considering the forces between atoms that make up matter in the three phases.

A rock is a solid. The rock's shape is due to the forces holding its atoms together. They resist attempts to push them closer together and hold them in close contact. Water is a liquid. The water is in an open container because of the forces between its atoms. A closed container is needed to hold a gas to prevent it from moving.

There are forces between the atoms that allow them to vibrate but not change their positions. A solid is resistant to all types of stress. The atoms that make up the solid are not able to move freely. Solids are resistant to compression because their atoms form part of a lattice structure in which the atoms are a fixed distance apart. The atoms would be forced into each other. Most of the examples we have studied involve solid objects which don't change much when stressed.

Solids and fluids have atomic and molecular characteristics. The Things Great and Small features of the text highlight the submicroscopic explanation. It is possible to see a description of pressure in a gas. This section is devoted to the submicroscopic explanation of liquids.

Liquids do not spring back to their original shape once the force is removed because the atoms are free to slide about and change neighbors, so they are a type of fluid. If the container has no holes below the surface of the liquid, it will remain in the container. Liquids are closely packed and resist compression.

Atoms in gases and charged particles are separated by large distances compared to the size of the particles. When the particles collide, the forces between them are very weak. Gases and plasmas are not only fluids, but they are also easy to compress because there is little force between the particles. Liquids will escape when placed in an open container. Liquids are not compressed as easily as gases are. They have a lot of energy and are difficult to contain.

As they change between solid, liquid, and gas phases, watch as atoms and molecules are heat, cool, and compressed.

There is a distinction between mass and density. We are tempted to think of bricks as heavier than feathers because of their higher density.

It's important to determine whether an object sinks or floats in a fluid. The mass per unit volume of an object is called density. The Greek letter rho is the symbol for density, the mass, and the volume occupied by the substance.

Mass per unit volume is called density.

The mass of the bricks and feathers is the same, but the volume occupied by the feathers is much higher. The representative values are given in Table 11.1. The metric system was designed so that water would have a density equivalent to. The kilogram was first created to be the mass of 1000 mL of water, which has a volume of 1000 cm3.

The feathers make a bigger pile than the bricks because of their lower density.

The density of an object may help identify its composition. The density of gold is 2.5 times that of iron and 2.5 times that of aluminum. The phase of the matter and its substructure are revealed by Density. The densities of liquids andsolids are roughly the same, consistent with the fact that their atoms are in close contact. The densities of gases are less than those of liquids andsolids because the atoms in gases are separated.

If the volumes of both piles are the same, the difference in mass is due to their different densities.

The density of water can be found in Table 11.1.

The equation for gives is solved.

The table has a density of water.

There is a large amount of water. In this example, the weight of the water is where the Earth's gravity is. It's reasonable to ask if the dam can provide a force equal to the weight. The answer is no. The force of the dam can be smaller than the weight of the water it holds back.

The world's largest hydroelectric plant was completed in 2008, generating power equivalent to 22 average-sized nuclear power plants. The concrete dam is 2.3 km across. This dam has a 660 km long reservoir. More than one million people were displaced by the creation of the dam.

There are many examples of pressures in fluids.

There is a force applied to an area.

There are many other units for pressure that are used in the same way.

millimeters of mercury (mm Hg) is used in the measurement of blood pressure, while pounds per square inch is used as a measure of tire pressure. When discussing fluids, pressure is important.

The International Space Station has no atmospheric pressure. Her air tank has a pressure gauge.

If we find the area acted upon, we can find the force exerted from the definition of pressure.

The area of the end of the cylinder is given.

The tank must be strong. The force exerted by a pressure is proportional to the area acted upon as well as the pressure itself.

The end of the tank exerts force on its inside surface. The force is exerted by a static or stationary fluid. We have already seen that fluids can't exert shearing forces. The fluid pressure is a quantity. The forces due to pressure are always in a straight line.

Swimmers and the tire feel the pressure.

The tire's pressure exerts forces on all the surfaces it contacts. The directions and magnitudes of the forces are given by the arrows. Shearing forces do not exert static fluids.

The swimmer is under pressure since the water would flow into the space he occupies if he were not there.

The forces on the swimmer are represented by the arrows. The forces underneath are larger due to greater depth, giving a net upward force that is balanced by the swimmer's weight.

As you change the volume, add or remove heat, change gravity, and more, you can see what happens when you put gas in a box. The properties of the gas vary in relation to each other, if you measure the temperature and pressure.

If you've ever been on a plane or in a swimming pool, you've experienced the effect of depth on pressure in a fluid. The weight of air above you exerts air pressure on you at the Earth's surface.

The weight of air above you decreases as you climb up in altitude. With increasing depth, the pressure on you increases. The pressure on you is caused by the weight of water above you and the atmosphere above you. If you notice an air pressure change on an elevator ride that transports you many stories, but you only need to dive a meter below the surface to feel a pressure increase, you're in good shape. Water is much denser than air.

The weight of the fluid is supported by its bottom. The pressure on the bottom is determined by the weight of the fluid.

The dimensions of the container are related to the volume of the fluid.

The pressure is the weight of the fluid. The equation has general validity beyond the special conditions. The surrounding fluid kept the fluid static even if the container weren't there. The equation shows the pressure due to the weight of the fluid at any depth below its surface. This equation holds great depths for liquids, which are nearly incompressible. One can apply this equation if the density changes are small over the depth considered.

The weight of the fluid is supported by the bottom of the container. The bottom must support the fluid since the vertical sides can't exert an upward force.

Pressure and force will be considered on the dam retaining water. The water is 80.0 m deep at the dam, which is 500 m wide.

The pressure at the average depth of 40.0 m is the average due to the weight of the water.

The value has already been found.

The force is small compared to the weight of the water in the dam. It depends on the average depth of the dam and the width and length of the lake. The force is dependent on the water's average depth and the dimensions of the dam. In the diagram, the thickness of the dam increases with depth to balance the increasing force due to the increasing pressure.

The dam must be able to hold onto the water. The force is small compared to the water behind the dam.

The weight of air above a given height is what causes atmospheric pressure. The atmospheric pressure at the Earth's surface varies a little due to the large-scale flow of the atmosphere.

The average weight of a column of air above the Earth's surface is equivalent to.

The average density of the atmosphere is 120 km. Compare this density with the air listed in the table.

We have to be atmospheric pressure, given, and known, and so we can use this to calculate.

The average density of air between the Earth's surface and the top of the Earth's atmosphere is 120 km. Table 11.1 shows the density of air at sea level. The density of air is the highest near the Earth's surface and plummets with altitude.

The pressure of the water is equal to 1.00 atm.

The density of the water is what creates the pressure.

The pressure is the same as 120 km of air. We can't change the density of the water since it's nearly incompressible.

The answer is yes. The atmosphere's weight must be supported since the water's weight is the same. Half of the total pressure is from the air above and the other half is from the water above. The fluid pressures always add in this way.

It is much easier if the fluid is kept out of sight. The heart increases blood pressure by pushing on the blood in an enclosed system. If you try to push on a fluid in an open system, the fluid will flow away.

Pressure can be increased by an applied force because a fluid cannot flow away.

The atoms in a fluid are free to move, so they transmit the pressure to the walls of the container. The pressure is undiminished.

A change in pressure is transmitted from the fluid to the walls of the container.

Pressure is important in fluids because of the principle of Pascal's principle. Since a change in pressure is undiminished in an enclosed fluid, we know a lot more about it.

The total pressure in a fluid is the sum of the pressures from different sources. The fact that pressures add is very useful.

He was home-schooled by his father who removed all of the mathematics textbooks from his house and forbade him to study mathematics until he was 15 years old. The boy's curiosity was raised by this, and by the age of 12 he was teaching himself geometry. Despite the early deprivation, Pascal made major contributions to the mathematical fields of probability theory, number theory, and geometry. He is well known for his contributions in the field of fluid statics, as well as being the inventor of the first mechanical digital calculator.

An enclosed fluid system used to exert forces is one of the most important technological applications of Pascal's principle. Car brakes are one of the most common systems that operate.

A typical system with two fluid-filled cylinders, capped with pistons and connected by a tube called a hydraulic line.

A downward force on the left piston creates a pressure that is transmitted to all parts of the enclosed fluid. This results in an upward force on the right Piston that is larger than the right Piston that has a larger area.

There will be no difference in pressure due to the difference in depth of the two pistons. As defined by, the pressure due to acting on area is simply. The pressure is transmitted undiminished throughout the fluid and all the walls of the container. A pressure is felt at the other part of the body.

The ratio of force to area is related to the height of the pistons and the amount of friction in the system. The force applied to them can be increased or decreased. To make the force bigger, the pressure is applied.

The brakes use a principle. The driver exerts a force on the brake pedal. The force is increased by the lever and the system. The same force output is created by each of the slave cylinders.

The master cylinder has a force of 500 N. Each slave cylinder has a diameter of 2.50 cm, while the master cylinder has a diameter of 0.500 cm.

The force is applied to the master cylinder.

It can be used to find the force.

The four slave cylinders exert force on this value. We can add as many cylinders as we want. A simple machine can increase force but cannot do more work than was done on it, if each has a 2.50- cm diameter. The slave cylinder moves through a smaller distance than the master cylinder. The smaller the distance each moves, the more slaves are added. Power brakes and bulldozers have a motorized pump that does most of the work in the system. The legs of a spider can be moved with the help of some things.

The system cannot do more work than is done because of the conservent of energy applied to it. The work output cannot exceed the work input. Extra energy is supplied by pumps when needed.

If you limp into a gas station with a flat tire, the tire gauge on the airline will read zero when you start filling it. Even though atmospheric pressure exists in the tire, the gauge would read zero if there was a gaping hole. There is no mystery here. When pressure is greater than atmospheric, tire gauges are designed to read zero and positive.

Every part of the circulatory system is affected by atmospheric pressure. Since atmospheric pressure adds to the pressure coming out of the heart and going back into it, there is no net effect on blood flow. The amount of blood pressure greater than atmospheric pressure is important. Blood pressure is made relative to atmospheric pressure.

It is very common for pressure gauge to ignore atmospheric pressure.

Positive and negative gauge pressure are used for pressures above and below it.

The pressure is relative to atmospheric pressure. Positive and negative gauge pressure are used for pressures above and below it.

The pressure in any fluid not enclosed in a container can be increased by atmospheric pressure. This happens because of a principle. If your tire gauge reads 34 pounds per square inch, then the absolute pressure is 34 pounds per square inch, or 48.7 pounds per square inch.

The sum of gauge pressure and atmospheric pressure is called absolute pressure.

Most of the time the absolute pressure in fluids can't be negative. The smallest absolute pressure is zero. The smallest possible gauge pressure is zero. There is no limit to how large a gauge pressure can be.

There are a lot of devices for measuring pressure. The principle of Pascal is important in these devices. The transmission of pressure through a fluid is undiminished. A measuring device can be put into a system to measure a person's arteries.

There are many types of mechanical pressure gauges in use today. Pressure results in a force that is converted into something else.

The aneroid gauge has flexible bellows connected to a mechanical indicator.

A manometer is a tube. They are open to the atmosphere. If the fluid is deeper on one side, there is more pressure on the deeper side, and the fluid flows away from that side until the depths are equal.

A manometer is used to measure pressure.

The fluid levels are no longer equal after pressure is transmitted to the manometer. The density of the fluid in the manometer is the difference between atmospheric pressure and atmospheric pressure by an amount.

A manometer with one side open is ideal for gauge pressures. Measure the gauge pressure to find it.

A manometer has one side open to the atmosphere. The jar's rigidity prevents pressure from being transmitted to the peanuts.

Mercury manometers can be used to measure blood pressure. The person making the measurement exerts pressure by squeezing the bulb, which is transmitted to the manometer and the main arteries in the arm. Blood flow below the cuff is cut off when the applied pressure exceeds blood pressure. The person makes the measurement and listens for blood flow to resume.

When blood flow begins as cuff pressure is lowered, thestolic pressure is measured. When blood flows without interruption, diastolic pressure is measured.

The average blood pressure of a young adult is 120mmHg at the top and 80mm at the bottom. The maximum output of the heart is represented by the first pressure and the elasticity of the arteries in maintaining the pressure between beats. The density of the mercury fluid in the manometer is 13.6 times greater than water, so the height of the fluid will be 1/6th of that in a water manometer. Mercury manometers are used to measure larger pressures because of the reduced height.

The density of mercury is very high.

The maximum blood pressure is systolic.

The minimum blood pressure is diastolic.

An inflatable cuff is placed on the upper arm to measure blood pressure. Pressures are transmitted to a mercury-filled manometer when blood flow is detected just below the cuff.

The help of the force is what makes thevenous infusions happen.

The IV bag is collapsible.

The pressure at entry to the vein must be greater than the pressure in the vein. We need to find the height of fluid that matches the gauge pressure.

The pressure needs to be converted into SI units.

The IV bag needs to be placed above the entry point into the arm to allow the fluid to enter the arm. IV bags are usually placed higher than this. You may have noticed that the bags used for blood collection are placed below the donor to allow blood to flow from the arm to the bag, which is the opposite direction of flow than required in the example presented here.

A barometer is used to measure atmospheric pressure. The device measures atmospheric pressure because there is a vacuum above the mercury in the tube. The mercury's height is such that. Important clues to weather forecasters can be found when the mercury rises or falls. Since atmospheric pressure varies with altitude, the barometer can be used as an altimeter. Mercury barometers and manometers are often used for atmospheric pressure and blood pressures. Some units of pressure are given conversion factors in Table 11.2.

A mercury barometer is used to measure atmospheric pressure. The pressure above the mercury is not enough to force mercury in the tube to a height.

Your arms feel heavy when you rise from the bath. You no longer have the support of the water.

The upward force on the bottom of an object in a fluid is greater than the downward force on the top of the object. The object will rise to the surface if the force is greater than the object's weight. The object will sink if the force on the object is less than the object's weight. The object will remain suspended if the force is equal to the object's weight. The force is always present when the object floats, sinks, or is suspended in a fluid.

The net upward force on any object is called the buoyant force.

With depth comes increased pressure due to the weight of the fluid. The upward force on the bottom of the cylinder is greater than the downward force on the top of the cylinder. Their force is different.

The object will rise if the weight is greater than the object. The object will sink if it is less than its weight.

The weight of the fluid displaced must be equal to the weight of the surrounding fluid. That is a statement of the principle.

fluid has a weight and fills the space it occupied. The weight of the fluid displaced by the object is supported by the surrounding fluid.

Any object in any fluid, whether partially or completely submerged, is valid.

The weight of the fluid is equal to the weight of the object.

In preparation for the Beijing Olympics, high-tech body suits were introduced. The suits should not give any advantage.

The density of water is less than that of aluminum foil. Take a piece of foil and roll it up into a ball.

You can mold the lump of clay into a boat. The shape of the boat makes it displace more water than the lump. Steel ships are the same.

The weight of water must be displaced to find the force. The densities of water and steel are given in Table 11.1. The steel's volume and the water's volume are the same. We can find its mass and weight by knowing the volume of the water.

First, we use the definition of density to find the steel's volume, and then we substitute values for mass and density.

This is the volume of water displaced because the steel is completely submerged. The mass of water is displaced from the relationship between its volume and density.

The steel's weight is much greater than the force of the water.

The density of steel is only two digits so the force is rounded to two digits.

The maximum volume of water the steel boat can displace is given here. The volume of water is the weight of the force.

The mass of water displaced is found from the relationship between density and volume.

The ship can carry a load nine times its own weight without sinking if it has a maximum buoyant force of ten times the steel's weight.

A piece of foil is very thin. A piece of foil is 10 cm by 15 cm. Take a test of your prediction.

Density is a crucial part of the principle. The density of an object is what determines whether it floats. It will float if its average density is less than the surrounding fluid. The fluid with a higher density contains more mass and weight in the same volume. The weight of the object is less than the weight of the fluid displaced. The object will sink if it's denser than the fluid.

The extent to which a floating object is submerged depends on the density of the fluid. The unloaded ship has a lower density and less of it is submerged than the loaded ship. Density can be used to derive a quantitative expression for the fraction submerged.

The volume submerged is the volume of fluid displaced. The relationship between densities can be obtained by substituting into the expression.

An unloaded ship floats higher in the water than a loaded ship.

The last relationship is used to measure densities. A hydrometer is used to measure the fraction of a floating object that is submerged.

The density of the object or substance is the same as the density of water. Specific gravity is not related to whatever units are used for. The object's gravity is less than one if it floats. Its specific gravity is greater if it sinks. The specific gravity of the floating object is equal to the fraction that is submerged. If an object's specific gravity is 1, then it will not sink or float. Scuba divers try to get this state so that they can swim. The specific gravity of fluids is an indicator of their condition.

The density of an object to a fluid is called specific gravity.

The hydrometer is floating in water. The glass hydrometer is weighted with lead at the bottom. It floats highest in the densest fluids and has been labeled so that specific gravity can be read from it.

When a woman's lungs are full of air, she should be submerged in freshwater with her volume submerged.

We can calculate the woman's density by knowing both the fraction submerged and the density of water.

Her density is not as high as the fluid density. Body density is an indicator of a person's percent body fat.

He is weighed in a "fat tank" where he is submerged as part of a body density determination. The subject needs to empty his lungs and hold a metal weight in order to sink. The metal weight and residual air in his lungs are measured separately. His corrected submerged weight, his weight in air, and pinch tests of strategic fat areas are used to calculate his percent body fat.

Less obvious examples include lava rising in a volcano and floating on the mantle beneath the mountain ranges. Earth has fluid characteristics.

The density of the coin is calculated using these two measurements.

A coin is weighed in air and then submerged in a liquid. If the fluid density is known, the density of the coin can be calculated. If the density of the coin is known, this technique can be used to determine the density of the fluid. All of the calculations are based on the same principle.

The weight of the fluid displaced is equal to the weight of the object. We call this measurement the object's apparent weight because it means that the object appears to weigh less when submerged. The weight of the fluid displaced is equal to the weight of the object. On balances that measure mass, the object suffers an apparent mass loss equal to the mass of fluid displaced.

This technique is used in the next example.

When the coin is submerged in water, the mass is 7.800 g.

We need the coin's mass and volume to calculate its density. The coin's volume is the volume of water displaced. The equation for density can be used to find the volume of water displaced.

The mass of water displaced is the volume of water. The apparent mass loss is the mass of the water displaced. The volume of water is. This is the amount of the coin that is submerged.

The density is very close to that of pure silver, which is appropriate for this type of ancient coin. Modern counterfeits are not pure silver.

This brings us back to how the principle came to be. The king of Syracuse gave Archimedes the task of determining if the royal crown maker was giving a crown of pure gold. The purity of gold can be determined by color, but other analytical techniques have not yet been developed. The ancient peoples realized that the density of gold was greater than any other substance. One day, while at the public baths, he was inspired by the support the water gave his body.

Learn how blocks work. You can modify the properties of the fluid and blocks with the help of the arrows.

An underwater spider has a bubble in his mouth. A technician draws blood from a small tube by touching it to a finger. A premature baby is trying to inflate her lungs. The attractive forces between atoms and molecules in liquids dominate all of these activities.

Liquids can be held in containers because they are cohesive. Liquid drops cling to window panes when they are caused by such forces. In this section, we look at the effects of cohesive and adhesive forces on liquids.

The attractive forces between the same type of molecule are called cohesive forces.

There are attractive forces between different types of molecule.

The soap bubbles in this picture are caused by the same forces. The surface of a liquid contracts to the smallest possible surface area. Molecules on the surface are pulled inward by forces.

Molecules inside the liquid have neighbors on all sides.

The surface of a liquid contracts to the smallest possible surface area. The surface tension is a general effect.

The surface tension is caused by forces between atoms and Molecules. The attractive forces pull the molecule closer together. This is an example of a submicroscopic explanation.

Surface tension effects can be explained by a model of a liquid surface acting like a stretched elastic sheet. The density of the iron needle is greater than that of water. The stretched surface tries to make the surface smaller or flatter. The weight of the needle on a small area would break the surface and cause it to sink.

The weight of an insect and an iron needle rest on the surface without being penetrated. They are supported by the surface of the liquid.

The strength of the cohesive force affects surface tension.

The liquid film tries to reduce the surface area of the wire. The surface tension of the liquid can be measured accurately.

Liquids form bubbles and droplets because of surface tension. The inward surface tension force causes bubbles to be spherical and raises the pressure of the gas trapped inside.

There is a bubble. When the bubble is the smallest, the pressure inside is greatest. The larger balloon fills the smaller balloon when air is allowed to flow between them.

A sliding wire device is used to measure surface tension. Since there are two liquid surfaces attached to the wire, the force needed to hold it in place is high. The force is almost constant as the film is stretched.

Two balloons of different sizes are attached to each end of a tube when the valve is closed. The smaller balloon shrinks in size when the air moves to fill the larger balloon. The flow is caused by the smaller balloon having a greater internal pressure than the larger balloon.

This pressure can be converted to millimetres Hg.

The surface tension can be found in Table 11.3, and so can be found directly from the equation.

If a hole were to be made in the bubble, the air would be forced out, the bubble would decrease in radius, and the gauge pressure would decrease to zero.

Our lungs contain hundreds of millions of mucus-lined sacs called alveoli, which are very similar in size and diameter. Allowing surface tension to contract these sacs will allow you to exhale without muscle action. Medical patients who have their breathing aided by a positive pressure respirator are allowed to exhale on their own. Air will leave the lungs even if there is paralysis. An occasional deep cleansing breath is needed to fully reinflate the alveoli.

We find it natural for our dogs and cats to take a cleansing breath before sleeping.

The bronchial tubes end in alveoli. The surface tension of their mucous lining helps in exhalation.

The walls of the alveoli have a liquid on them that acts as a surface-tension reducing substance. The need for the surfactant is caused by the tendency of small alveoli to collapse and the air to fill into the larger alveoli making them even larger. The surface tension on the alveoli decreases during exhalation as the molecules slide back together. The wall tension is changed by the surfactant so that small alveoli don't collapse and large alveoli don't expand too much. This tension change is not shared by detergents, which lowers surface tension.

The lung surfactant's surface tension decreases as the area decreases. Small alveoli don't collapse and large alveoli aren't able to over expand.

If water enters the lungs, the surface tension is too high and you can't breathe. This is a serious problem in saving someone's life. The lungs of newborn infants who are born without this surfactant are difficult to inflate. It is a leading cause of death for infants in premature births. The spraying of a surfactant into the infant's breathing passages has achieved some success. The problem with alveoli is produced by emphysema. The sacs combine to form larger sacs as the walls of emphysema get worse. The ability of emphysema victims to exhale is reduced by the larger sacs that produce smaller pressure. The pressure and volume of air that can be exhaled is a common test for emphysema.

Even the oil from your fingers can affect the surface properties of the needle, so it needs to be very clean. The bristles will stick together if you pull the brush out.

The surface tension effect goes away as the bristles dry out. Look at the shape of the loop. Put a drop of detergent in the middle of the loop. Put a drop of detergent in it. For each experiment, the water needs to be replaced and the bowl washed to free it of detergent.

The forces between water and wax are smaller than those between paint and water. Competition is important in the behavior of liquids. The angle between the liquid surface and the surface is an important factor in studying the roles of these two forces. The larger the cohesive force, the bigger the droplets. The smaller the relative strength, the easier it is to flatten the drop.

The contact angle is the angle between the liquid surface and the surface.

The contact angle is related to the strengths of the forces. The ratio of cohesive to adhesive forces is larger when it is larger.

The tendency of a fluid to be raised or suppressed in a narrow tube. When the tube touches a drop, blood is drawn into it.

capillary action is the tendency of a fluid to be raised or suppressed in a narrow tube.

The contact angle given in the table is a factor that affects the effect. If the fluid is less than, it will be suppressed. Mercury has a large surface tension and a large contact angle with glass. The surface of a column of mercury curves downward when placed in a tube. The surface tension reduces the surface area. The curved liquid surface in a capillary tube is flattened by surface tension.

The mercury is suppressed in the tube as surface tension flattens it. The shape of the mercury surface would not be affected by surface tension. Surface tension exerts an upward force when it flattens the surface.

The height to which capillary action can raise or suppress a liquid in a tube is limited by its weight.

We might see how it makes sense if we look at the different factors. The height is proportional to the surface tension. Since a smaller tube holds less mass, the higher the fluid can be raised. The height is related to fluid density, since a larger density means a larger mass in the same volume.

The larger the tube, the taller it gets. The height is not significant for large-radius tubes.

To answer this question, calculate the radius of a capillary tube that would raise 100 m to the top of a giant redwood, assuming that it's density is, its contact angle is zero, and its surface tension is the same as that of water.

Every quantity is known except for, and the height to which a liquid will rise as a result of capillary action is given by.

This result is not reasonable. Tubes with radii as small as are formed when bark in trees moves through the xylem. The value is about 180 times larger than the radius needed to raise the water. It is not possible for capillary action alone to be responsible for getting to the top of trees.

The question has not been completely resolved, but it appears that it is pulled up like a chain. The entire chain is pulled up a notch as each molecule enters a leaf.

The cohesive forces seem to be too small to hold the molecule tightly together in most situations. The pull provided by the cohesive force of water molecule is very strong. Experiments have shown that negative pressures can be used to pull the sap from the tallest trees.

Blood pressure is one of the most common medical exams.

The decrease in heart attack and stroke deaths achieved in the last three decades is largely due to the control of high blood pressure. Valuable medical indicators can be provided by the pressures in various parts of the body. In this section, we look at a few examples together with some of the physics that accompanies them.

The units most commonly quoted are measured in millimetres Hg.

The values of 120mm Hg and 80mm Hg for systolic and diastolic pressures are typically produced by common arterial blood pressure measurements. There are health implications of both pressures. The risk of stroke and heart attack increases when the pressure is high. It is a problem if it is too low. The change may be beneficial to the tone of the circulatory system because it produces no ill effects. It can indicate that a person is bleeding internally and needs a transfusion. The ballooning of the blood vessels may be the result of the transfusion of too much fluid into the circulatory system. Blood vessels are not dilating properly when the pressure is high. This can cause the heart to stop pumping blood.

Blood flow through the system as well as the position of the person cause the pressure differences in the circulation system. The weight of the blood causes the pressure in the feet to be larger than at the heart.

A long time standing can cause blood to accumulate in the legs. Soldiers who are required to stand for long periods of time have been known to faint. Increased pressure on the bandages around the calf can help the veins send blood back up to the heart. Doctors recommend tight stockings for long-haul flights.

Blood pressure can be measured in the major veins, the heart chambers, arteries to the brain, and the lungs. The pressures are usually only monitored during surgery or for patients in intensive care. To transmit pressures to external measuring devices, qualified health care workers thread thin tubes, called catheters, into appropriate locations.

Left-heart failure causes a rise in the pressure in the left side of the heart and a drop in the aortal pressure. Implications of these and other pressures on flow in the circulatory system will be discussed in more detail.

The right side of the heart pumps blood through the lungs to the rest of the body.

The circulatory system has typical pressures. The two pumps in the heart increase the pressure in the body. Medical implications from long-term deviations from these pressures are discussed in some detail in the Fluid Dynamics and Its Biological and Medical Applications. Only the arteries can be measured.

The net pressure can become so large that it can permanently damage the nerve.

The back of the eye has an area and the net pressure is 85.0mm Hg.

The force is given by.

Intraocular pressure maintains the shape of the eye. A build up in pressure in the eye is called Glaucoma, and can be caused by blocked fluid in the eye.

The force is the mass. The damage would be caused by a mass of 680 g resting on the eye.

People over the age of 40 should have their intraocular pressure tested frequently. The eye's response is the most important part of most measurements. A noncontact approach uses a puff of air and a measurement is made of the force needed to hit the eye. The eye will rebound more vigorously if the intraocular pressure is high. It is possible to detect excessive intraocular pressures.

The eye pressure can be read with a tonometer.

A force of 3.00-N can break an eardrum.

Since we know the force and area, the pressure can be found directly from its definition. The gauge pressure is something we are looking for.

The water pressure varies with depth below the surface.

When there is a fluid build up in the middle ear, there can be increased pressure on the eardrum.

When you inhale, the pressure falls to below atmospheric pressure, which causes air to flow into the lungs. When you exhale, it increases above atmospheric pressure.

Several mechanisms control lung pressure. The volume of the lungs is increased by the muscle action in the rib cage. Positive pressure is created by the surface tension in the alveoli. When you blow up a balloon, blow out a candle, or cough, you can add muscle action to the positive pressure.

If the alveoli were not attached to the inside of the chest wall, the lungs would collapse. The gauge pressure in the liquid attaching the lungs to the chest wall is negative, ranging from to during exhalation and inhalation. One or both lungs may collapse if air is allowed to enter the chest cavity. To inflate the lungs of trauma victims and surgery patients, suck air out of the chest.

The pressure between the lungs and chest wall is lower because of the surface tension in the lungs. The pressure between the chest wall and lungs is negative, but not as negative as during inhalation.

Normally, there is a 5- to12-mm Hg pressure in the fluid surrounding the brain. One of the uses of the fluid is to supply flotation to the brain. The density of the brain is nearly the same as the force supplied by the fluid. The brain rests on the inside of the skull if there is a loss of fluid. The pressure is measured using a needle that is inserted between the back of the neck.

We are often aware of this bodily pressure. There is a relationship between our awareness of the pressure and an increase in it. As the bladder fills to its normal capacity, bladder pressure climbs from zero to 25mm Hg. It also causes muscles around the bladder to contract, raising the pressure to over 100mm Hg, accentuating the sensation. Bladder pressure can be measured with a catheter, by injecting a needle through the bladder wall, or by using a measuring device. A hazard of high bladder pressure is that it can cause urine to go back into the kidneys and cause serious damage.

The high values of initial force and the small areas to which this force is applied make these pressures the largest in the body. This pressure can damage the discs in the spine. Under normal circumstances, the forces between the vertebrae in the spine are large enough to create pressures. Lifting properly and avoiding extreme physical activity are some of the ways in which excessive pressure can be avoided. Food and waste can be caused by pressure caused by muscle actions. Stomach pressure is tied to the sensation of hunger. The pressure in the chest is usually negative. If atmospheric pressure is greater than middle ear pressure, there can be force on the eardrum. The decrease in external pressure can be seen during plane flights due to a decrease in the weight of air above the Earth's surface. The Eustachian tubes connect the middle ear to the throat and allow us to equalize pressure in the middle ear.

The human body has many pressures associated with it.

A fluid is a state of matter that yields to sideways or where is the pressure, is the height of the liquid. Both fluids are gases.

Density is the mass per unit volume of a substance or Pressure is force per unit area.

The SI unit of density is the change in pressure applied to an enclosed fluid that isundiminished to all portions of the fluid.

The force is applied to the area over which it is measured.

The SI unit of pressure is pascal and the gauge pressure is relative to atmospheric.

The sum of gauge pressure and Depth in a fluid atmospheric pressure is called the Variation of Pressure.

The pressure is the weight of the fluid divided by the spring arrangement and the area of the bottom of the scale.

It can be used to measure pressure.

Cohesive forces cause the liquid to contract to the smallest possible surface area.

The surface tension is a general effect.

The net upward force on any object is called buoyant force. The object will rise to the surface if the strength of the float is greater than the strength of the narrow tube. If the force is less than the object's.

The object will remain suspended if the force is equal to 11.9 Pressures in the Body. Blood pressure is one of the most common objects that floats, sinks, or is suspended in a fluid.

The weight of the fluid it displaces can be compared to the pressures in various parts of the body.

The shape of the eye is maintained by fluid pressure and intraocular pressure.

When the circulation of fluid in the eye is blocked, it can lead to a condition called Capillary Action Glaucoma.

Some of the other pressures in the body are called cohesive forces.

Give an example of density being used to identify the substance.

When a glacier is sitting on land.

jogging on soft ground and wearing padded between the cork and liquid

Normal dancing or walking is easier on toes than toe dancing.

How do you convert pressure units that are larger than the slave cylinder?

If both sides are open to the weight of the atmosphere above your body, atmospheric pressure exerts a force equal to a manometer.

Considering the amount of blood under the levee.

It takes more force to pull the plug in a full bathtub than it does when it's empty.

The river level is very high. Under the levee, part of their weight is supported. Sandbags are placed around the leak, and force, yet the downward force on the bottom of the tub the water held by them rises until it is the same level as the river.

Water beads up on an oily sunbather, but not on her neighbor, whose skin is not oiled.

The density of oil is less than that of water, yet a loaded "weightless" environment sits lower in the water than an empty one.

Birds such as ducks, geese, and swans are able to sit on their exhales without muscles because of their higher pressure inside their lungs.

The troy ounce is the price of gold.

Mercury is supplied in flasks with weighted densities of its components.

Your body's volume and density are determined by the nucleus of your breath.

A method of finding the density of an atom is straightforward. A remnant of a supernova can have the same density of a rock as a nucleus.

Coffee has the same density as her high-heeled shoes.

The density of the rubbish record is a factor that affects the pressure exerted by a phonograph needle.

A 2.50-kg steel gasoline can hold 20.0 L of gasoline, what pressure is exerted on the record in full?

The force must be applied to the nail with the water depth. In particular, show that this force is given circular tip of 1.00mm diameter to create a pressure of by, where is the density of water, and is the length of the dam. The face of the dam may be vertical if you assume the hammer striking the nail is brought to rest.

The deepest part of the ocean is located in the Philippines.

The need for highspeed pumps is eliminated when water towers store water above the level of consumers.

The humor in a person's eye exerts a force of 0.300 N.

The slave has a wide by 0.900-m long gas tank that can hold up to 50.0 liters and what pressure is exerted on the bottom of a 0.500-m cylinder.

He is amazed when he exerts a force of 800 N. The bottom of the jug breaks away when the cork is put into place.

Hg by putting a force on the blood that was 100 times larger than the one put into it.

When the ice floats in reduced by the same factor that the output force is freshwater, what fraction of ice is submerged. The volume of the fluid can be assumed to be constant.

Logs sometimes float vertically in a lake because one end of the system has become denser than the other.

Pressure volume is submerged with a density of floats with its Pressure.

The air pockets in the bird bones give them an average density of mercury. An ornithologist might take a bird bone for each.

A rock with a mass of 540 g is found to have those for an adult. Consider the smaller mass when submerged in water.

The years can be calculated using the principle, although their use has declined in recent years. Early models had a bad habit of exploding. If a piece of iron with a mass of 390.0 g in air is found to be enough to force the latches onto the circular lid, the pressure cooker will be able to survive. The lid has a lot of weight.

If you measure a standing person's blood, you can identify the fluid's density.

Assume that the lungs are empty and there is no loss of pressure.

A submarine is stuck on the bottom of the ocean and has a hatch that is 25.0 m below the surface.

The density of some fish is less than that of the water. To stay submerged, air pressure inside must exert a force. There is a submarine.

The bicycle has a mass of 80.0 kilograms and the gauge pressure in the tires is.

The volume of the rubber can be neglected.

You can mark on the side how much water she assumes the pressure is the same as it is when held in a spherical bubble.

The walls are fluid-lined.

What if the alveolus acts like a spherical bubble?

The cork is floating in the water with a mercury magnet on it.

The iron anchor's weight will be determined by the radius of the tube that supports it when submerged in the left.

If you can find a tube for less than a gold value but more than a meter, you will be able to get it at a better price. If you want to know if it is almost pure as water, you need to know the mass of the contact angle is zero, and the surface tension is the same as an ingot in and out of water.

The mattress has a weight of 2 kilograms.

You might think of bubbles of water, alcohol, and soapy water. The ends of the bubbles form the most stable and the effects of the cylinder have equal areas.

The water could be raised by capillary action.

Until they form a single bubble, the pressure in the esophagus should be smaller.

The pressure in the spinal fluid is measured by capillary action in the same glass figure. If the pressure in the fluid is greater than 10.

The pressure between the lungs and chest wall is created by the diaphragm and chest muscles.

The manometer is open to the atmosphere and can be used to measure the force on the small object relative to the spine column. If the person sits up, the pressure in pascals will be greater.

One way to force air into an unconscious person's lungs is to squeeze on a balloon that is connected to a major arteries and has a maximum blood pressure of 150. How much force must you exert on the balloon to create a gauge pressure of 4.00 cm?

The disk between the spine is through a hollow reed and is subjected to a 5000-N compressional force. If the disk has your lungs more than 60.0 cm below the surface, you can't inhale this way.

The pressure in the fluid surrounding an infant's brain remains the same.

A full-term fetus usually has a mass of 3.50 kilograms.

There is pressure in this liquid.

Some people want to remove water from the mine shaft. A moving at and brought to rest in 2.80 pipe is lowered to the water 90 m below.

You are pumping up a bicycle tire with a hand pump, and you know that it has a 2.00- cm radius.

Their boat strikes a log in the lake.

The size and density of the log and what is needed to keep a person's head and arms above water are some of the variables to be considered.

The alveoli in emphysema victims form larger sacs. The larger average diameter of the alveoli causes them to have surface tension that leads to the loss of pressure.

The normal surface tension of the fluid lining the alveoli, the average alveolar radius in normal individuals, and the average in emphysema sufferers are some of the things to consider.