Air And Aerodynamics Test Quiz

The same volume of air can take up different amounts of space. The more pressurized the air is, the less space it takes up. This does not mean that some air disappears at high pressures, just that the existing air becomes more dense. The air inside of the plastic cup exerted enough pressure on the water outside of the cup that it only compressed slightly. If the cup were 10 or 20 meters underwater, the growing pressure from the water on top would probably pressurize the air to the extent that the water would touch the sponge. With the small pressure caused by the water in the sink, the air did not compress to a large extent, thus leaving the sponge dry

When Emily blew over the top of the paper, the air flow created a decrease in pressure on the upper surface of the paper. According to Bernoulli's principle, as the air speed increases, the pressure decreases. This pressure difference caused the paper to lift up towards Emily's face, demonstrating the principle.

The tires made of vulcanized rubber can support a much larger pressure than your lungs. This means that it is not possible to inflate a tire to the sufficient pressure by simply using ones' breathing.

Drag is the opposing force against moving objects. It is caused by the air resistance as the atmosphere is displaced by a moving object. The less air that needs to be pushed out of the way, the less energy is wasted to air resistance. Streamlines are curves used in structural designs. A streamlined shape allows air to pass over an object more easily, reducing drag.

Bernoulli's principle states that as fluids move faster, they decrease in pressure. Lift on an airplane follows this principal because the wing is shaped such that the upper side has a curve while the lower side is flat. This causes air on top of the wing to move faster while air below moves slower since it needs to move a lesser distance to pass the wing. The lower pressure on top of the wing causes airplanes to move upward as the higher pressure below the wing pushes up on the plane.

Animals have adaptations that allow them to live more easily in their environment. In the case of birds, there are two major adaptations that make them suited to flying. The first is the hollow bones that reduce the mass of the bird, and thus the gravitational pull downward. The second is the shape of the wings. Bird wings follow a similar shape to those of an airplane, except that the bottom side of the wing is not filled in. Because the air passing over the wing must travel over a longer curve than those below the wing, the air pressure above the wing is less than that below as faster moving air above the wing reduces air pressure. The higher pressure beneath the wings causes the bird to gain lift.

It is believed that many species of flightless birds became flightless as their natural predators became extinct or competition for resources became less fierce. As the life pattern of the ostrich changed, its bones began to become heavier and the wings to become too small to lift the heavy mass of the bird. The modern ostrich can no longer fly because the lift produced is not sufficient.

Air exerts pressure on objects that stand in its way. This pressure is referred to as air resistance when such pressure is seen as undesirable. While Rene was playing with the air, the efficiency of the car would have been slightly reduced as the aerodynamics of the car were compromised.

Because there is almost no air in space, a spaceship will continue moving in almost uniform motion until either gravity changes its path or a thrust missile is fired off in the opposite direction of desired movement. The lack of air resistance also poses a problem to turning the spacecraft as there is no air to push off of.

Combustion reactions are exothermic. In other words, when ever something is burned, heat is released. As the candle burns, oxygen and wax (solidified paraffin) is converted to carbon dioxide and heat. Eventually the candle burns out as all the oxygen is gone. The air then cools down as the heat source is lost. This cooling process results in the contraction of the air as it cools. Water then fills the empty space left behind and the water level inside the jar rises.

The hair spray is pressurized.This means that particles of hair spray are forced into the can, making the particles inside the can very dense. Because the particles in the surrounding air are less tightly packed, particles from the can escape into the lower atmospheric pressure (pressure of the atmosphere) and distribute themselves outside of the can. In the process, they become less tightly packed.

Air exerts pressure on objects that stand in its way. This pressure is referred to as air resistance when such pressure is seen as undesirable. While Rene was playing with the air, the efficiency of the car would have been slightly reduced as the aerodynamics of the car were compromised. Hand Position D is not streamlined and would cause air resistance as air particles are forced to travel around the hand. It would also not create much lift as the angle is too steep. Generally, an angle in the 40 to 50 degree range creates the most lift.

The manipulated variable in this experiment is the temperature of the air in the balloon. In order to observe any change in the size of the balloon, the constant variables of the balloon composition and air volume must be the same.

If Stephanie keeps the constant variables, she will find that a balloon left at room temperature will stay the same. The balloon that is cooled will become smaller and the balloon that is heated will become bigger.

Air expands as it is heated. This will cause the small bubbles in the marshmallow to grow in size and puff the marshmallow. This is nothing like the marshmallows that you roast over a camp fire and eat, but a huge puffball of solid bubbles.

Do not try this experiment at home without permission. It can ruin your microwave as the marshmallow expands and sticks to the sides of the appliance.

In flight, lift and weight (gravity) play a tug-of-war role. If the lift force is greater than weight (gravity), then the airplane rises. If the weight (gravity) force is greater than lift, then the airplane falls (or stays on the ground). The following diagram illustrates this. Note that for our purposes, weight and gravity are synonymous.

While some oncoming wind is diverted over buildings, the majority is forced into the channels between the buildings, causing unusually fast wind gusts as more air is forced into a smaller channel. This is why winds in the city center are often stronger than those in the suburbs.

Because oxygen is necessary for combustion, the gas resources will not ignite unless air is allowed into the oil beds. Luckily, the oil beds are far from the surface and little air is available for combustion.

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Aerodynamic structures experience the least air resistance. This is ideal for high winds because the air will pass easily over and around the structure without exerting a large force on it.

Streamlining involves the addition of curves to structural design to reduce air resistance to objects that need to be aerodynamic. Balls are fast moving structures that must be designed to be aerodynamic with the addition of streamlines. Such objects would be tested for air resistance levels with a wind tunnel.

As long as the balloon is strong enough to hold the same pressure as the volleyball, air will fill the balloon until the pressure is equal. If the pressure in the volleyball is so strong that the balloon pops, then the pressurized air will drain out of the volleyball until the atmospheric pressure is reached. This is quite possible as the balloon is not nearly as thick as the volleyball.

Oxygen composes approximately 20% of the gases in the atmosphere. Because the rusting of iron is a process that needs oxygen, if there is no oxygen, the reaction cannot occur. By placing the heating pad in an airtight plastic bag, the available oxygen in the bag will quickly run out and since no more oxygen can get in, the rest of the iron in the package will not be oxidized. This means that the leftover iron will remain un-rusted and the reaction will promptly restart the next time the package is used, releasing heat when it is needed.

A wind tunnel tests air resistance by blowing high-speed air at various objects. This is useful in the design of aerodynamic structures ranging from cars to skis. In wind tunnel testing, the pressure that the air exerts on these objects measured. An aerodynamic design will receive the least air resistance (pressure).

Combustion (burning) occurs when fuel burns in oxygen to produce carbon dioxide and water. Nitrogen makes up approximately 78% of Earth's atmosphere. If the atmosphere was 100% oxygen, things would ignite very easily. Also, some metals that are somewhat stable in our current atmosphere (such as iron) would be very combustible. This is because the process of rusting converts metals and oxygen into metal-oxygen compounds (rust). Imagine having all of the iron on earth rust 5 times faster! The nitrogen in our atmosphere helps regulate combustion by limiting the amount of oxygen available in the air for combustion and corrosion reactions.

Because the air at higher altitudes has less air above it, it in turn is less pressurized and thus less dense. The human body needs a good supply of oxygen in order for cellular respiration to occur, and the reduced oxygen densities at higher altitudes can cause health problems as not enough oxygen is available for the body.

Air exerts pressure on objects that stand in its way. This pressure is referred to as air resistance when such pressure is seen as undesirable. While Rene was playing with the air, the efficiency of the car would have been slightly reduced as the aerodynamics of the car were compromised. Generally, an angle in the 40 to 50° range creates the most lift. Because Hand Position C has about a 10° slope downwards, it would probably cause negative lift as his hand is pulled downwards.

Combustion (burning) occurs when fuel burns in oxygen to produce carbon dioxide and water. Nitrogen makes up approximately 78% of Earth's atmosphere. If the atmosphere was 100% oxygen, things would ignite very easily. Also, some metals that are somewhat stable in our current atmosphere (such as iron) would be very combustible. This is because the process of rusting converts metals and oxygen into metal-oxygen compounds (rust). Imagine having all of the iron on earth rust 5 times faster! The nitrogen in our atmosphere helps regulate combustion by limiting the amount of oxygen available in the air for combustion and corrosion reactions.

Water is difficult to compress, whereas air is easily compressed by hand.

The pressure exerted on the bottle when it squeezed compresses the air inside the pen cap rather than the water surrounding it. This means that the air in the pen cap takes less space and that more water can move in to take its place. Once enough water has accumulated, the buoyant force becomes insufficient to hold up all of the water in the cap, and the diver sinks. When the bottle is released, the pressure on the air in the cap subsides, and the trapped air expands once again, expelling the accumulated water and causing the cap to rise again.

Bernoulli's principle is unrelated; it states that faster moving fluids are less dense than slower moving fluids.

Ohm's law deals with electricity.

As more matter is forced in an enclosed space, the pressure increases. Each time the pump is pressed, more air is squeezed into the tire which results in higher pressure. It also becomes more difficult to pump as more and more air is struggling to escape the pressure in the tire and diffuse into the lower pressure of the atmosphere. This pressure of air trying to escape results in the tire becoming more firm as the pressure is exerted on the rubber.

Controlled variables are those that remain constant. Manipulated variables are those that change. Since the amount of water in the basin stays the same, this is a constant variable while the amount of air inside the jar is a manipulated variable.

At the beginning of the experiment, the can is partially filled with air and partially filled with liquid water. After heating the can for a while, the can becomes filled with hot air (including water vapor) and hot liquid water. The heated contents put a lot of outward pressure on the can walls. By placing the can upside-down in the basin, he created a sudden region of low pressure in the can, because as the water and gases cool and condense they take up less room. The pressure in the can suddenly decreases but the pressure outside of the can stays the same. This causes the can to crumple under the pressure and implode because high-pressure regions move toward or push in on low-pressure regions.

Bernoulli's principle states that as fluids move faster, they decrease in pressure. Thus, the faster moving air between buildings would be of lesser pressure.

Lift on an airplane follows this principal because the wing is shaped such that the upper side has a curve while the lower side is flat. This causes air on top of the wing to move faster than the air moving the wing. The lower pressure on top of the wing causes airplanes to move upward as the higher pressure below the wing pushes up on the plane.

Compressed gases can be very dangerous. In a sport like paintball, which is already quite dangerous, the possibility of the air tank bursting into flame is not desirable. Thus, stable gases, such as carbon dioxide, are used. Other benefits include the fact that carbon dioxide is easy to manufacture and is non-toxic in the low concentrations that are dispersed from the gun.

As air heats up, the particles get sent further apart. In this process, the air becomes less dense. As the hot air immediately above the asphalt convects into the cold air above, the shimmering effect occurs as the air forms small scale wind patterns.

The keyboard cleaner is pressurized. This means that particles of air are forced into the can, making the particles inside the can very dense. Because the particles in the surrounding air are less tightly packed, particles from the can escape into the lower atmospheric pressure (pressure of the atmosphere) and distribute themselves outside of the can. In the process, they become less tightly packed and thus warmer. The process is endothermic (takes in heat) as energy is absorbed into the expanding particles.

Bernoulli's principle states that as fluids move faster, they decrease in pressure. Lift on an airplane follows this principal because the wing is shaped such that the upper side has a curve while the lower side is flat. This causes air on top of the wing to move faster while air below moves slower since it needs to move a lesser distance to pass the wing. The lower pressure on top of the wing causes airplanes to move upward as the higher pressure below the wing pushes up on the plane.