True/False
Indicate whether the
statement is true or false.
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1.
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The upward buoyant force of a fluid opposes the downward force of gravity on an
object.
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2.
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Fluids exert pressure because their particles have weight, although they are
motionless.
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3.
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Submarines could be crushed due to the increase in fluid pressure at certain
ocean depths.
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4.
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The buoyant force on an object is equal to the weight of the fluid displaced by
the object.
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5.
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Buoyancy determines whether an object sinks or floats in fluids.
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6.
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A hydraulic lift transmits fluid pressure in different amounts in different
directions.
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7.
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The total area of both pistons in a hydraulic lift is the same.
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8.
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The particles in fluids are tightly packed together.
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9.
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As depth in a fluid increases, the pressure it exerts
decreases.
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10.
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The relationship between buoyancy and the weight of a displaced fluid is called
Archimedes' principle.
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Multiple Choice
Identify the
choice that best completes the statement or answers the question.
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11.
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1. Pressure is force
a. | divided by mass. | c. | times mass. | b. | divided by area. | d. | times area. |
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12.
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Pressure is measured in which of the following units
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13.
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At high altitudes, there are
a. | more particles of air. | c. | the same number of air particles as at lower
altitudes. | b. | fewer particles of air. | d. | fewer particles of air and increased air pressure. |
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14.
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Fluid pressure increases as
a. | altitude increases. | c. | depth increases. | b. | altitude and depth
increase. | d. | depth
decreases. |
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15.
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5. The direction of fluid pressure is
a. | upward | c. | toward the sides. | b. | downward | d. | in all
directions. |
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16.
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6. The direction of a buoyant force on an object placed in a fluid is
a. | unrelated to other forces on that object. | c. | in the same direction as the
gravitational force on that object. | b. | opposite to the gravitational force on that
object. | d. | in the same
direction as the weight of the object. |
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17.
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7. Archimedes' principle applies to
a. | submerged objects only. | c. | floating objects
only. | b. | liquids and gases. | d. | liquids only. |
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18.
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According to Archimedes' principle, the buoyant force on an object
is
a. | always greater than the weight of a submerged object. | c. | equal to the weight of the
displaced fluid. | b. | greater than the weight of the displaced fluid. | d. | less than the weight of the displaced
fluid. |
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19.
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An object will float in a fluid if the density of the fluid is
a. | greater than the density of the object. | c. | equal to or less than the density
of the object. | b. | less than the density of the object. | d. | unrelated to either the mass or the volume of
the object. |
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20.
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The density of water is
a. | 1.0 g | c. | 1.0 g/cm | b. | 1.0 cm | d. | 1.0 cm /g |
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21.
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When a submarine sinks,
a. | its weight is greater than the weight of the displaced water. | c. | its weight is equal
to the weight of the displaced water. | b. | its weight is less than the weight of the
displaced water. | d. | its weight
is less than the buoyant force. |
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22.
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Although the density of steel is 7.8 g/cm3 and the density of water is
I
gicm3, steel cruise ships float because
a. | most of the ship is steel, but part is water. | c. | the total density of the steel,
air, and load is greater than the density of water. | b. | the total density of the steel, air, and load
is less than the density of water. | d. | the total density of air and load is equal to the density of
steel. |
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23.
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In order to float in air, balloons are filled with
a. | carbon dioxide because carbon dioxide is less dense than air. | c. | helium because
helium is less dense than air. | b. | equal Parts of helium and carbon
dioxide. | d. | neither helium nor
carbon dioxide. |
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24.
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If 51 g of a substance takes up 75 cm  of space, the density of the
substance is a. | 1.47 g/cm | c. | 1.47 cm /g. | b. | 0.68 g/cm | d. | 0.68 cm /g. |
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25.
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The principle applied to the design of an airplane wing was developed by
a. | Archimedes | c. | Newton | b. | Bernoulli | d. | Boyle |
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26.
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The faster a fluid moves, the
a. | less pressure it exerts. | c. | less is its
density. | b. | more pressure it exerts. | d. | greater is its density. |
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27.
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Because the density of salt water is greater than that of fresh water, a
ship
will
a. | float higher in salt water than in fresh water. | c. | be submerged more rapidly in salt
water than in an equal amount of esh water. | b. | float higher in fresh water than in salt
water. | d. | require more salt
water than fresh water to equal its weight. |
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28.
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Comparing the densities of hot and cold air, hot air
a. | is equal in density to cold air. | c. | is less dense than cold
air. | b. | is more dense than cold air. | d. | has particles closer
together. |
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29.
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An example of a hydraulic system is
a. | person floating in a salty body of water. | c. | a ball bearing. | b. | a hot air
balloon. | d. | the lift on a
barber's chair. |
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30.
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Buoyancy is
a. | the tendency of objects to sink in fluids. | c. | a force in the same direction as
gravity. | b. | the force of a fluid that pushes an object up. | d. | caused by the fact that objects have less mass
in a fluid |
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31.
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An object will float in water if its density is
a. | 0.8 g/cm | c. | 2.0 g/cm | b. | 1.1 g/cm | d. | 1.5 g/cm |
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32.
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What is the pressure if a force of 20 N is exerted over an area of 10 cm  ? a. | 2 N /cm | c. | 20 N /cm
| b. | 10 N/cm | d. | 200 N/cm |
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33.
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What is the force exerted on a surface measuring 1000 cm2 if the pressure is 2
N/cm2?
a. | 500 N | c. | 2000 N | b. | 500 cm | d. | 2000 cm |
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34.
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Which of the following would cause an increase in pressure?
a. | increasing the area without changing force | c. | decreasing the force without
changing area | b. | decreasing the area without changing force | d. | decreasing both force and area by the same
amount |
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35.
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Hydraulic devices apply a small force over a small area to
a. | ensure that the pressure is equal in all directions. | c. | increase
pressure. | b. | produce a large force over a large area | d. | produce a large force over a small
area. |
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36.
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The pressure exerted by a fluid is due to the motion of its particles and
the
a. | downward pull of gravity on them. | c. | color of the
substance. | b. | volume of the substance. | d. | friction of the substance. |
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37.
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An airplane wing is designed to make the air move
a. | faster over the top than under the bottom. | c. | the same speed over the top as
under the bottom. | b. | slower over the top than under the
bottom. | d. | slower both over
the top and under the bottom. |
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38.
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A submarine submerges by
a. | taking in more water | c. | decreasing its density. | b. | decreasing its
speed. | d. | decreasing its
mass |
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39.
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Fluids will move
a. | from areas of higher pressure to areas of lower pressure. | c. | both of
these | b. | from areas of lower pressure to areas of higher pressure. | d. | neither of
these |
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40.
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Density equals
a. | volume divided by mass. | c. | mass divided by
volume. | b. | mass times volume | d. | volume minus mass. |
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