Term
| An object surrounded by a fluid will displace a volume of fluid that is |
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Definition
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Term
| Fluid pressure is always directed |
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Definition
| equally in all directions |
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Term
| If an object weighing 50 N displaces a volume of water with a weight of 10N, what is the buoyant force on the object? |
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Definition
1500 N/500 Pa=3N/m2
1500 N/6Nm2 = 250 Pa |
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Term
| A helium-filled balloon will float in air because |
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Definition
| helium is less dense than air |
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Term
| Materials that can flow to fit their containers include |
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Definition
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Term
| What two factors determine the amount of lift achieved by an airplane? |
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Definition
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Term
| Where is water pressure greater, at a depth of 1 m in a large lake or at a depth of 2 m in a small pond? Explain. |
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Definition
| greater at depth of 2 m in small pond; water pressure does not depend on total amount of fluid present |
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Term
| Is there buoyant force on an object at the bottom of an ocean? Explain your answer. |
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Definition
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Term
| Why are liquids used in hydraulic brakes instead of gases? |
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Definition
| Liquids are used in hydraulic brakes because liquids cannot be compressed easily. Gases are compressible. |
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Term
| Any object that is more dense than the surrounding fluid will ____________. |
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Definition
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Term
| Any object that is less dense than the surrounding fluid will ____________. |
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Definition
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Term
| Wings are often shaped to allow airplanes to take advantage of _______________ pressure in moving air in order to achieve flight |
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Definition
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Term
| Lift on an airplane is determined by ______________ and ______________. |
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Definition
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Term
| How does thrust increase lift? |
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Definition
| Greater thrust means greater speed, which means faster air and increased lift. |
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Term
| The forward force produced by a plane’s engine is ___________ . |
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Definition
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Term
| The upward force acting on an airplane wing due to air flow is called__________________ . |
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Definition
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Term
| The fast-moving air above an airplane wing exerts less pressure than the slow-moving air below the wing, according to ________________________ |
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Definition
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Term
| An irregular or unpredictable flow of fluids is known as___________________ . |
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Definition
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Term
| What does Bernoulli’s principle say about the speed of a moving fluid? |
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Definition
| The faster the fluid’s speed is, the lower the pressure |
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Term
| How does the water pressure change as you dive farther underwater? |
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Definition
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Term
| How is lift created around wing of an airplane? |
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Definition
| faster moving air above the wing crates an area of low pressure above the wing |
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Term
| What affects the flight of an airplane? |
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Definition
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Term
| A high-performance jet needs _________ wings. |
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Definition
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Term
An irregular or unpredictable flow of fluids is known
as________________________ . |
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Definition
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Term
| How do birds reduce drag? |
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Definition
| Birds adjust their wing feathers in response to turbulence. |
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Term
| The force that opposes or restricts motion in a fluid is called _____________________________ . |
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Definition
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Term
| Pascal’s principle is used by __________to move or lift objects. |
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Definition
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Term
| Hydraulic devices can _______________ force |
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Definition
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Term
| When brakes are used to stop a car, _____________ is in effect. |
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Definition
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Term
| How does drag affect an aircraft’s speed, and how can drag be reduced? |
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Definition
| Turbulence causes drag and reduces lift. Airplane flaps can be adjusted to reduce drag and increase lift. |
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Term
| How do birds reduce drag? |
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Definition
| Birds adjust their wing feathers in response to turbulence. |
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Term
| How does wing size affect how birds fly? |
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Definition
| A bird with small wings must flap its wings at a rapid pace to fly. A bird with large wings can flap less often. |
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Term
| A glider needs ________________ wings. |
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Definition
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Term
| n a fluid, buoyant force exists because the pressure is greater at ____________ the of an object than the pressure at the top. |
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Definition
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Term
| n a fluid, buoyant force exists because the pressure is greater at ____________ the of an object than the pressure at the top. |
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Definition
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Term
| Why does a helium balloon float in air? |
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Definition
| The balloon floats because helium is less dense than air. |
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Term
| Why does an ice cube float in water? |
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Definition
| The ice cube floats because it is less dense than water. |
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Term
| How does the density of a rock affect its ability to float? |
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Definition
| A rock is denser and therefore heavier than water, so it sinks. |
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Term
The upward force that fluids exert on all matter is
called_______________________ . |
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Definition
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Term
| he weight of displaced fluid determines the ___________ on an object. |
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Definition
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Term
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Definition
| The air inside the bubble is a fluid. Fluids exert equal pressure in all directions, so the bubble expands equally in all directions and creates a sphere. |
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Term
| Why are tornadoes like giant vacuum cleaners? |
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Definition
| Air pressure inside a tornado is much lower than the air pressure outside the tornado. This difference creates a vacuum-cleaner type effect, where objects are pushed into the tornado. |
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Term
| An object floats when its density |
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Definition
| force that particles of a fluid exert over a certain area due to their weight and motion |
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Term
| An object floats when its density |
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Definition
| force that particles of a fluid exert over a certain area due to their weight and motion |
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Term
| Moving particles of matter create ___________ by colliding with one another and with the walls of their container. |
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Definition
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Term
| _______________ exert pressure equally in all directions |
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Definition
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Term
| Fluids flow from areas of ___________ pressure to areas of low pressure. |
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Definition
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Term
| Hydraulic devices transmit changes of pressure through ______________. |
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Definition
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Term
| All fluids exert an upward force called _______________________. |
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Definition
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Term
| Buoyant force is caused by differences in fluid _____________. |
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Definition
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