Physic 1310 Chapter 13

How does the water pressure 1 m below the surface of a small pond compare with the water pressure 1 m below the surface of a huge lake?

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*Buoyant force is greatest on a submerged a) 1-kg block of lead b) 1-kg block of aluminum c) is the same on each

a

A liter-sized block of ordinary wood floats in water. The amount of water displaces is a) less than 1 liter b) 1 liter c) more than 1 liter d) depends on the water density

a

An egg is placed at the bottom of a bowl filled with water. Salt is slowly added to the water until the egg rises and floats. From this experiment, one can conclude that __________. A) the density of salt water exceeds the density of egg. B) calcium in the eggshell is repelled by sodium chloride. C) buoyant forces do not always act upward. D) salt sinks to the bottom. E) none of the above

a

Compared to the density of water, the density of a fish is a) the same. b) more. c) less.

a

How does the water pressure 1 m below the surface of a small pond compare with the water pressure 1 m below the surface of a huge lake? a) The pressure will be the same. b) The pressure will be less. c) The pressure will be greater. d) The pressure will be zero in both cases.

a

How much air must a 100-ton blimp displace to float and neither rise nor sink? a) 100 tons b) Its volume of air c) 10,000 tons d) 10 tons

a

How much force is needed to hold a nearly weightless but rigid 1-L carton beneath the surface of water? a) 9.8 N b) 11 N c) 20 N

a

If you swim beneath the surface in saltwater, will the pressure be greater than in fresh water at the same depth? a) The pressure will be greater. b) The pressure will be less. c) The pressure will be the same. d) The pressure will be zero.

a

The block of styrofoam floats on water while a same size block of lead lies submerged in the water. The buoyant force is greatest on the a) lead b) styrofoam c) is the same for both

a

The pressure at the bottom of a jug filled with water does NOT depend on a) surface area of the water. b) the height of the liquid. c) the acceleration due to gravity. d) water density. e) none of the above

a

Water pressure on a submerged object is greatest against its a) bottom. b) top. c) same against all surfaces d)sides. e) none of the above

a

What is the mass of 1 L of water? What is its weight in newtons? a) 1 kg; 10 N b) 1000 kg; 10,000 N c) 0 kg; 0 N d) 10 kg; 1 N

a

When a boat sails from fresh water to salt water, the boat will float a) higher in the water. b) at the same water level. c) lower in the water.

a

When holes are drilled through the wall of a water tower, water will spurt out with the greatest speed from the hole closest to a) the bottom of the tower. b) the top of the tower. c) the middle of the tower. d) all the same

a

When you stand with only one of your feet on a weighing scale, the scale reading is a) the same as with both feet. b) half. c) doubled. d) none of the above

a

Which will remain the same for two identical books, one lying flat and the other standing on an end? a) weight b) pressure c) both of these d) neither of these

a

A block of aluminum with a mass of 1 kg is placed in a beaker of water filled to the brim. Water overflows. The same is done in another beaker with a 1-kg block of lead. Does the lead displace more, less, or the same amount of water? a) the same amount b) less c) more

b

How does pressure relate to force? a) Pressure is force per unit length. b) Pressure is force per unit area. c) Pressure is the same as force. d) Force is pressure per unit area.

b

How is the density of a fish controlled? How is the density of a submarine controlled? a) A fish changes its weight, whereas a submarine changes its volume. b) A fish changes its volume, whereas a submarine changes its weight. c) A fish changes its weight, whereas a submarine changes its mass. d) A fish changes its volume, and a submarine changes its volume, too.

b

If an object suspended by a scale shows a weight of 3 N in air, and 2 N when submerged in water, the buoyant force on the submerged object is __________. a) 2 N b) 1 N c) 3 N d) more than 3 N

b

If you float a piece of wood in a container brim-full of water that rests on a weighing scale, some water will spill. Then the weight reading on the scale will a) decrease. b) remain unchanged. c) increase.

b

Surface tension is a direct result of a) viscosity. b) cohesive forces between molecules in a liquid. c) adhesive forces between molecules in a liquid or solid. d) Archimedes' principle.

b

What is the condition in which the buoyant force on an object does equal the weight of the object? a) It will float. b) The object is neutrally buoyant, so it will neither sink nor float. c) It will float almost completely out of the water. d) It will sink.

b

A block of aluminum with a volume of 10 cm3 is placed in a beaker of water filled to the brim. Water overflows. The same is done in another beaker with a 10-cm3 block of lead. Does the lead displace more, less, or the same amount of water? a) less b) more c) the same amount

c

A lobster crawls onto a bathroom scale submerged at the bottom of the ocean. Compared to its weight above surface, the lobster will have an apparent weight under water that is ____. a) greater. b) the same. c) less.

c

A mountain that floats on the mantle indicates that the density of the mantle is a) less than that of the mountain. b) about the same as that of the mountain. c) greater than that of the mountain. none of the above

c

Buoyant force is greatest on a submerged a) 1-cubic centimeter block of lead b) 1-cubic centimeter of block of aluminum c) is the same on each

c

How does pressure at the bottom of a body of water relate to the weight of water above each square meter of the bottom surface? a)The pressure is the weight times the depth divided by 1 m2. b) The pressure is the weight density divided by 1 m2. c) The pressure is the weight of the water divided by 1 m2. d) The pressure is the weight times the depth.

c

How does the buoyant force on a submerged object compare with the weight of the water displaced? a) The buoyant force is greater than the weight of the water displaced. b) The buoyant force is less than the weight of the water displaced. c) The buoyant force is equal to the weight of the water displaced. d) Both are zero.

c

Is the buoyant force on a submerged object equal to the weight of the object itself or is it equal to the weight of the fluid displaced by the object? a) It is equal to the weight of the object. b) It is equal to both the weight of the object and the weight of the fluid displaced. c) It is equal to the weight of the fluid displaced. d) Neither. It is equal to the mass of the fluid displaced.

c

Pumice is a volcanic rock that floats, which means its density is a) equal to the density of water. b) more than the density of water. c) less than the density of water. need more information.

c

The pressure in a liquid depends on liquid a) depth. b) density. c) both of these d) neither of these

c

What is the cause of surface tension? a) An oil film b) The temperature of the water c) Molecular attraction d) Molecular repulsion

c

When you float in fresh water, the buoyant force that acts on you is equal to your weight. When you float higher in the denser water of the Dead Sea, the buoyant force that acts on you is a) greater than your weight. b) less than your weight. c) equal to your weight.

c

A dam is thicker at the bottom than at the top mainly because a) surface tension exists only on the surface of liquids. b) it looks better. c) water is denser at deeper levels. d) water pressure increases with depth. e) none of the above

d

The reason a life jacket helps keep you afloat is a) the jacket has the same density as an average human. b) the jacket repels water. the jacket makes you weigh less. c) if you sink, the jacket sinks. d) the density of both you and the jacket together is less than your density alone.

d

The volume of water displaced by a floating 20-ton boat a) is the volume of the boat. b) is 20 cubic meters. c) depends on the shape of the ship's hull. d) is the volume of 20 tons of water. e) none of the above

d

Water pressure in a lake is greater __________. a) midway to the bottom b) at the surface c) at any point, for pressure is the same throughout d) at the bottom

d

The mass of a cubic meter of water is a) 1 kg. b) 10 kg. c) 9800 N. d) 100 kg. e) 1000 kg

e