A dam is thicker at the bottom than at the top partly because
water pressure is greater with increasing depth
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3
The pressure in a liquid depends on liquid
both of these (density and depth)
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4
One liter of water has a mass of
1 kilogram
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5
Blood pressure is normally greater in your
feet
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6
What is the buoyant force acting on a 10-ton ship floating in the ocean?
10 tons
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7
When an object is partly or wholly immersed in a liquid, it is buoyed up
by a force equal to the weight of liquid displaced
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8
The mass of a cubic meter of water is
1000 kg
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9
Pumice is a volcanic rock that floats. Its density is
less than the density of water
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10
The reason that buoyant force acts upward on a submerged object is that
upward pressure against the bottom is greater than downward pressure against the top of the submerged object
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11
A completely submerged object always displaces its own
volume of fluid
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12
Compared to the density of water, the density of a fish is
the same
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13
The buoyant force on an object is least when the object is
partly submerged
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14
The buoyant force on a rock is least when the rock is submerged
buoyant force does not depend on depth
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15
The reason a life jacket helps you float is
the density of both you and the jacket together is less than your density alone
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16
When holes are drilled through the wall of a water tower, water will spurt out the greatest horizontal distance from the hole closest to
the bottom of the tower
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17
The density of a submerged submarine is about the same as the density of
water
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18
A floating ice cube contains small pieces of iron. During melting the water level will
fall
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19
The pascal is a pressure unit equal to one
newton per square meter
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20
To multiply the input force of a hydraulic lift, the input end should be the one having the
smaller diameter piston
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21
The ratio of output force to input force of a hydraulic press will be equal to the ratio of the output and input piston
areas
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22
A hydraulic press multiplies a force by 100. This multiplication is done at the expense of
the distance through which the force acts
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23
A consequence of the surface tension of water is
all of these
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24
Surface tension is a direct result of
cohesive forces between molecules in a liquid
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25
Surface tension of liquids
decreases as the liquid temperature increases
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26
A large block of wood and a smaller block of iron on weighing scales both register 1 ton. Taking buoyancy of air into account, which has the greater mass?
wood
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27
In drinking soda or water through a straw, we make use of
atmospheric pressure
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28
At normal atmospheric pressure and temperature, 1 cubic meter of air has a mass of about
1\.25 kg
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29
Marshmallows in a vacuum become
larger
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30
About how high can water at sea level be theoretically lifted by a vacuum pump?
10\.3 m
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31
When a suction cup sticks to a wall it is
pushed to the wall by the atmosphere
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32
When water is turned on in a shower, the shower curtain moves toward the water spray. This partly involves
pressure changes in moving fluids
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33
The Bernoulli effect causes passing ships to be drawn together when the ships are close and moving in
either the same or opposite directions (either of these)
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34
The tarp covering on a trailer or truck puffs upward for fast-moving vehicles, which illustrates
Bernoulli’s principle
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35
The principle of continuity states that for fluid flow to be continuous it must in narrow regions of flow
both of these (speed and slow down)
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36
As fluid gains speed, its internal pressure flow
decreases
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37
When a gas in a container is squeezed to half its volume with no change in temperature, the gas pressure
doubles
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38
When a gas in a container is squeezed to half its volume, its density
doubles
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39
When a gas in a container expands to twice its volume, its density
halves
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40
When boarding an airplane you bring a bag of chips. While in flight the bag puffs up, because
air pressure in the air-tight bag is greater than cabin air pressure
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41
A swimmer cannot snorkel more than a meter deep because air
at the surface will not freely enter the higher pressure region in the compressed lungs
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42
A bubble of air released from the bottom of a lake
becomes larger as it rises
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43
A scuba diver losing her air supply while far beneath the water surface is advised when ascending to
allow air to escape her lungs
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44
An empty jar is pushed open-side downward into water so that trapped air cannot escape. As it is pushed deeper, the buoyant force on the jar
decreases
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45
Archimedes’ principle applies to
all of these
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46
the buoyant force of the atmosphere on a body is equal to the
weight of air displaced
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47
The flight of a blimp best illustrates
Archimedes’ principle
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48
An object in a vacuum has no
buoyant force
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49
A car with closed windows makes a left hand turn. a helium-filled balloon in the car moves to the
left
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50
Compared with air pressure on the outside, air pressure inside an inflated stretched balloon is
greater
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51
Atmospheric molecules do not fly off into outer space due to
Earth gravitation cohesive forces
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52
Atmospheric pressure is caused by the
weight of the atmosphere
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53
The air in your classroom has
all the above
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54
About what percentage of molecules in the air make up the atmosphere below a 6-kilometer altitude?
more than 50%
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55
The energy source responsible for molecular motions in Earth’s atmosphere is
Studied by 2 people
