Physics Holtz Exam 3

If a 1-L container is immersed halfway into water, what is the volume of the water displaced? What is the buoyant force on the container? 10 L displaced, 1 N buoyant force 1 L displaced, 10 N buoyant force 0.5 L displaced, 5 N buoyant force 0.5 L displaced, 10 N buoyant force

0.5 L displaced, 5 N buoyant force

One liter of water has a mass of 1 kilogram. 14.7 grams. 500 grams. none of the above

1 Kilogram

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 __________. 2 N more than 3 N 3 N 1 N

1 N

Buoyant force is greater on a submerged is the same on each 1-kg block of lead. 1-kg block of aluminum.

1-kg block of aluminum.

The buoyant force acting on a 10-ton ship floating in the ocean is less than 10 tons. depends on density of sea water 10 tons. more than 10 tons.

10 Tons

The mass of a cubic meter of water is 9800 N. 100 kg. 1000 kg. 10 kg. 1 kg.

100 KG

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

100 Tons

What is the weight of water displaced by a 100-ton floating ship? less than 100 tons more than 100 tons 100 cubic meters depends on the ship's shape 100 tons

100 tons

A scale from which a rock is suspended reads 5 N when the rock is out of water and 3 N when the rock is submerged. Buoyant force on the rock is 5 N. 3 N. 4 N. 2 N.

2 N

How much force is needed to hold a nearly weightless but rigid 1-L carton beneath the surface of water?

9.8 N

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

A fish changes its volume, whereas a submarine changes its weight.

Surface tension is a direct result of A.)cohesive forces between molecules in a liquid. B.)viscosity. C.)adhesive forces between molecules in a liquid or solid. D.)Archimedes' principle.

A.)cohesive forces between molecules in a liquid.

Why isn't there a horizontal buoyant force on a submerged object? Forces on the sides are zero at every point. Force vectors on the top and bottom cancel one another. Forces on the top and bottom add and cancel gravity. Force vectors on the sides cancel one another.

Force vectors on the sides cancel one another.

If you float a piece of wood in a container half-full of water that rests on a weighing scale, the weight reading on the scale will increase. remain unchanged. decrease.

Increase

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? Neither. It is equal to the mass of the fluid displaced. It is equal to the weight of the fluid displaced. It is equal to the weight of the object. It is equal to both the weight of the object and the weight of the fluid displaced.

It is equal to the weight of the fluid displaced.

What is the cause of surface tension? Molecular repulsion Molecular attraction An oil film The temperature of the water

Molecular attraction

How does pressure relate to force? Pressure is force per unit length. Pressure is force per unit area. Pressure is the same as force. Force is pressure per unit area.

Pressure is force per unit area.

What is the relationship between liquid pressure and the depth of a liquid? Between liquid pressure and weight density? Pressure is proportional to both depth and weight density. Pressure is inversely proportional to depth and proportional to weight density. Pressure is inversely proportional to both depth and weight density. Pressure is proportional to depth and inversely proportional to weight density.

Pressure is proportional to both depth and weight density.

What will these objects do in water: an object denser than water, an object less dense than water, an object that has the same density as water. Sink, float, neither float nor sink Sink, float, sink Float, sink, float Float, sink, neither float nor sink

Sink, float, neither float nor sink

What geometrical shape has the smallest surface area for a given volume? Sphere Disk Cube Cylinder

Sphere

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

The buoyant force is equal to the weight of the water displaced.

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

The object is neutrally buoyant, so it will neither sink nor float.

What happens to the pressure in all parts of a confined fluid if the pressure in one part is increased? The pressure in the other parts remains the same. The pressure everywhere decreases to conserve total pressure. The pressure everywhere increases by the same amount. The pressure everywhere increases by different amounts depending on the area of each part.

The pressure everywhere increases by the same amount.

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? The pressure is the weight of the water divided by 1 m2. The pressure is the weight times the depth divided by 1 m2. The pressure is the weight density divided by 1 m2. The pressure is the weight times the depth.

The pressure is the weight of the water divided by 1 m^2.

Why does the buoyant force act upward on an object submerged in water? The pressure upward on the deeper bottom is greater than the downward pressure on the top. Water shields the object from gravity. The pressure downward on the deeper bottom is less than the upward pressure on the top. The pressure upward on the top is greater than the downward pressure on the deeper bottom.

The pressure upward on the deeper bottom is greater than the downward pressure on the top.

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

The pressure will be greater. Density of ocean water is 1027 kg/m3 (H2O is 1000 kg/m3)

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? The pressure will be greater. The pressure will be the same. The pressure will be zero in both cases. The pressure will be less.

The pressure will be the same. P doesn't depend on volume, but depth

How does the volume of a completely submerged object compare with the volume of water displaced? The volumes are equal. The volumes of both add to zero. The volume of the submerged object is greater than the volume of displaced water. The volume of the submerged object is less than the volume of displaced water.

The volumes are equal.

Does the buoyant force on a submerged object depend on the volume of the object or on the weight of the object?

Volume

A hospital patient confined to bed will be less likely to develop bed sores with a soft mattress. firm mattress. water bed. none of these will help.

Water Bed

The attraction between unlike substances is called cohesion. adhesion. depends on the substances.

adhesion

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

at the bottom

An egg rests at the bottom of a bowl filled with water. When salt is slowly added to the water the egg rises and floats, from which we conclude salt water is denser than an egg. salt water is denser than fresh water. both of these neither of these

both

The pressure in a liquid depends on liquid density. depth. both of these neither of these

both

A fish normally displaces its own volume of water. weight of water. both of these neither of these

both of these

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

bottom

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

bottom

The attraction between like substances, stickiness, is called adhesion. depends on the substances. cohesion.

cohesion

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 less than your weight. greater than your weight. equal to your weight.

equal

While standing, your blood pressure is normally greatest in your feet. head. same in each heart.

feet

The concept of pressure involves both force and volume. force and area. area and volume.

force and area

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

greater than that of the mountain.

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

higher

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

is the volume of 20 tons of water.

A lobster crawls onto a bathroom scale on the ocean floor. Its weight compared to its weight above the surface is the same. greater. less.

less

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

less

The amount of water displaced by a liter-sized block of ordinary wood floating in water is 1 liter. less than 1 liter. depends on the water density more than 1 liter. none of the above

less than 1 liter

A person floats higher in the dense water of the Dead Sea because of a greater buoyant force. more volume of water is displaced. less volume of water is displaced.

less volume of water is displaced.

Compared to an empty ship, the same ship loaded with Styrofoam will float at the same level in the water. higher in the water. lower in the water.

lower in the water.

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

mass 1 kg weight 10 N volume 1000 cm3 density 1 kg/L wt density 10 N/L

Surface tension is caused by __________. molecular attractions water's tendency to remain wet the interaction between air and a water surface temperature variations in liquids

molecular attractions

Buoyant force acts upward on a submerged object because pressure against its bottom is greater than pressure against its top. the weight of fluid displaced reacts with an upward force. it acts in a direction to oppose gravity. none of the above

pressure against its bottom is greater than pressure against its top.

Buoyant force is greater on a submerged 1-cubic centimeter block of same on each lead. aluminum.

same

Two life preservers have identical volumes, but one is filled with Styrofoam while the other is filled with sand. When the two life preservers are fully submerged, the buoyant force is greater on the one filled with A.)sand. B.)same on each as long as their volumes are the same C.)Styrofoam.

same on each as long as their volumes are the same

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

surface area of the water

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

the density of both you and the jacket together is less than your density alone.

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

the same

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

the same as with both feet

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 increase. decrease. remain unchanged.

unchanged

A completely submerged object always displaces its own density of fluid. volume of fluid. weight of fluid. all of the above none of the above

volume of fluid.

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

water pressure increases with depth.

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

weight