MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Transcription

1 Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The concept of pressure involves both 1) A) force and area. B) force and volume. C) area and volume. 2) Which will remain the same for two identical books, one lying flat and the other standing on an end? A) pressure B) weight C) both of these D) neither of these 2) 3) When you stand with only one of your feet on a weighing scale, the scale reading is 3) A) the same as with both feet. B) doubled. C) half. D) none of the above 4) Sara lies on a bed of sharp nails without harm because 4) A) her weight is distributed over hundreds of nails. B) many of the nails don't make contact with her body. C) she exercises mind over matter. D) none of the above 5) A hospital patient confined to bed will be less likely to develop bed sores with a 5) A) soft mattress. B) water bed. C) firm mattress. D) none of these will help. 6) One liter of water has a mass of 6) A) 500 grams. B) 1 kilogram. C) 14.7 grams. D) none of the above 7) While standing, your blood pressure is normally greatest in your 7) A) same in each B) feet. C) head. D) heart. 8) Water pressure on a submerged object is greatest against its 8) A) top. B) sides. C) same against all surfaces D) bottom. 9) A dam is thicker at the bottom than at the top mainly because 9) 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. 10) The pressure in a liquid depends on liquid 10) A) density. B) depth. C) both of these D) neither of these 1

2 11) The pressure at the bottom of a jug filled with water does NOT depend on 11) A) water density. B) the acceleration due to gravity. C) the height of the liquid. D) surface area of the water. 12) The mass of a cubic meter of water is 12) A) 10 kg. B) 1 kg. C) 100 kg. D) 1000 kg. E) 9800 N. 13) Buoyant force acts upward on a submerged object because 13) A) it acts in a direction to oppose gravity. B) pressure against its bottom is greater than pressure against its top. C) the weight of fluid displaced reacts with an upward force. D) none of the above 14) 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 middle of the tower. B) the top of the tower. C) the bottom of the tower. D) all the same 15) There is a legend of a Dutch boy who bravely held back the Atlantic Ocean by plugging a leak near the top of a dike with his finger until help arrived. Which is the more likely scenario? A) although the force on his finger would have been huge, the pressure would have been small enough for this to occur B) the force on his finger would have been less than 1 N C) the huge size of the Atlantic Ocean makes this impossible D) both force and pressure on his finger would have been great, but not too great for a public-spirited Dutch lad 14) 15) 16) A completely submerged object always displaces its own 16) A) weight of fluid. B) density of fluid. C) volume of fluid. D) all of the above 17) The buoyant force on an object is least when the object is 17) A) submerged near the surface. B) partly submerged. C) submerged near the bottom. D) none of the above 18) The least buoyant force on a rock is when it is submerged 18) A) near the surface. B) near the bottom. C) halfway to the bottom. D) none of the above 19) The buoyant force acting on a 10-ton ship floating in the ocean is 19) A) more than 10 tons. B) 10 tons. C) depends on density of sea water D) less than 10 tons. 2

3 20) The volume of water displaced by a floating 20-ton boat 20) A) is 20 cubic meters. B) depends on the shape of the ship's hull. C) is the volume of 20 tons of water. D) is the volume of the boat. 21) When a boat sails from fresh water to salt water, the boat will float 21) A) higher in the water. B) lower in the water. C) at the same water level. 22) A block of Styrofoam floats on water while a lead block of the same size block lies submerged in the water. The buoyant force is greatest on the A) same for both B) Styrofoam. C) lead. 22) 23) When an object is partly or wholly immersed in a liquid, it is buoyed up 23) A) by a force equal to the weight of liquid displaced. B) by a force equal to its own weight. C) and floats in accord with Archimedes' principle. D) all of the above 24) What is the weight of water displaced by a 100-ton floating ship? 24) A) more than 100 tons B) depends on the ship's shape C) 100 tons D) less than 100 tons E) 100 cubic meters 25) 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 A) 4 N. B) 2 N. C) 3 N. D) 5 N. 25) 26) Buoyant force is greater on a submerged 26) A) 1-kg block of aluminum. B) is the same on each C) 1-kg block of lead. 27) Buoyant force is greater on a submerged 1-cubic centimeter block of 27) A) lead. B) same on each C) aluminum. 28) Buoyant force is greater on a submerged 10-newton block of 28) A) aluminum. B) same on each C) lead. 29) 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. The density of the rock is A) 3.5 times the density of water. B) 2.5 times the density of water. C) the density of water. D) 1.5 times the density of water. 29) 3

4 30) Pumice is a volcanic rock that floats, which means its density is 30) A) more than the density of water. B) equal to the density of water. C) less than the density of water. D) need more information. 31) A fish normally displaces its own 31) A) weight of water. B) volume of water. C) both of these D) neither of these 32) Compared to the density of water, the density of a fish is 32) A) the same. B) less. C) more. 33) Lobsters live on the bottom of the ocean, which means their density is 33) A) greater than the density of sea water. B) less than the density of sea water. C) equal to the density of sea water. 34) A lobster crawls onto a bathroom scale on the ocean floor. Its weight compared to its weight above the surface is A) less. B) greater. C) the same. 34) 35) The density of a submerged submarine at rest is about the same as the density of 35) A) water. B) a floating submarine. C) a crab. D) iron. 36) 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 A) salt water is denser than an egg. B) salt water is denser than fresh water. C) both of these D) neither of these 36) 37) Ice cubes submerged at the bottom of a liquid indicate that the liquid 37) A) is only partly displaced by the submerged ice. B) is warmer than the ice. C) produces insufficient buoyant force on the ice. D) is less dense than ice. 38) A 5-N block of wood is difficult to fully submerge in a pool of mercury because the buoyant force on the block when submerged is A) much more than 5 N. B) less than 5 N. C) 5 N. 38) 39) The reason a life jacket helps keep you afloat is 39) A) the jacket has the same density as an average human. B) the density of both you and the jacket together is less than your density alone. C) the jacket makes you weigh less. D) if you sink, the jacket sinks. E) the jacket repels water. 4

5 40) 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) same on each as long as their volumes are the same B) Styrofoam. C) sand. 41) Two life preservers have identical volumes, one filled with Styrofoam and the other filled with sand. When the two life preservers are worn by swimmers, one swimmer floats with part of the preserver above water, and the other swimmer sinks. In this case the buoyant force is greater on the life preserver filled with A) Styrofoam. B) same for both C) sand. 40) 41) 42) A mountain that floats on the mantle indicates that the density of the mantle is 42) A) less than that of the mountain. B) greater than that of the mountain. C) about the same as that of the mountain. D) none of the above 43) Compared to an empty ship, the same ship loaded with Styrofoam will float 43) A) at the same level in the water. B) lower in the water. C) higher in the water. 44) 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 A) increase. B) remain unchanged. C) decrease. 45) 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) increase. C) remain unchanged. 46) The fact that the weight of a brim-full container of water is unchanged whether or not something floats in it is nicely employed in A) hydraulic devices. B) Scotland's Falkirk Wheel. C) all floating devices. D) none of the above 47) A key feature of the Falkirk Wheel in Scotland is that opposite gondolas have the same weight when both are brim-full of water A) and boats in each have about equal weights. B) regardless of the weights of boats or no boats in each. C) and at least one boat is in each gondola. D) none of the above 44) 45) 46) 47) 48) An important condition for operation of the Falkirk Wheel is that 48) A) water in each gondola have the same depth. B) no water spill when a ship enters a gondola. C) ships carried are more or less equal in weight. D) all of the above 5

6 49) The amount of water displaced by a liter-sized block of ordinary wood floating in water is 49) A) depends on the water density B) 1 liter. C) less than 1 liter. D) more than 1 liter. 50) 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) equal to your weight. B) greater than your weight. C) less than your weight. 50) 51) A person floats higher in the dense water of the Dead Sea because 51) A) more volume of water is displaced. B) of a greater buoyant force. C) less volume of water is displaced. 52) When an ice cube in a glass of water melts, the water level 52) A) falls. B) rises. C) remains the same. 53) An ice cube floating in a glass of water contains many air bubbles. When the ice melts, the water level will A) rise. B) remain unchanged. C) fall. 54) An ice cube with large air bubbles in it floats in a brim-full container of water. When the ice cube melts, A) water level in the container goes down. B) no change in water level occurs. C) water spills over. 55) A large ice cube containing an iron railroad spike floats in a brim-full container of water. When the ice cube melts, A) water level in the container drops. B) no change in water level occurs. C) water spills over. 53) 54) 55) 56) A floating ice cube contains small pieces of iron. The water level after melting will 56) A) remain unchanged. B) rise. C) fall. 57) When a large floating ice cube with unfrozen water inside melts, the water level in its container 57) A) goes up. B) remains unchanged. C) goes down. 58) A heavy iron ball is placed in an aluminum pie pan that floats in a bucket. The water level at the side of the bucket is marked. Then the ball is removed and allowed to sink in the bucket. The water line at the side of the bucket A) rises. B) is the same. C) goes down. 58) 59) When scrap iron in a boat is thrown overboard in a swimming pool, the pool level 59) A) rises. B) falls. C) remains unchanged. 6

7 60) When a barrel of water in a rowboat in a swimming pool is poured overboard, the pool level 60) A) rises. B) falls. C) remains unchanged. 61) When a load of wood is thrown overboard from a boat in a swimming pool, the pool level 61) A) rises. B) falls. C) remains unchanged. 62) If a battleship sinks in a canal lock, the water level in the lock will 62) A) rise. B) fall. C) remain unchanged. 63) If the part of an iceberg that extends above the water were suddenly removed, the 63) A) pressure on the bottom of the iceberg would increase. B) iceberg would sink. C) density of the iceberg would change. D) buoyant force on the iceberg would decrease. 64) If a weighted air-filled balloon sinks in deep water, it will 64) A) likely burst if water pressure is great enough. B) be acted on by a continuously decreasing buoyant force. C) likely sink to an equilibrium level before reaching bottom. D) none of the above 65) A block of wood with a piece of iron tied to the top of it floats in a bucket of water. If the wood and iron are turned over so that the iron is submerged beneath the wood, the water level at the side of the bucket A) remains the same. B) falls. C) rises. 65) 66) The pascal is a pressure unit equal to 66) A) 1 kilogram per square meter. B) 1 newton per square centimeter. C) 1 newton per square meter. D) 1 kilogram per square centimeter. 67) Pascal's principle applies to 67) A) gases. B) liquids. C) both of these D) none of these 68) When you observe the applications of pistons in lifting operations you're seeing 68) A) Pascal's principle in action. B) how energy can be increased. C) both of these D) neither of these 69) In a hydraulic-press operation, it is impossible for the 69) A) force output to exceed the force input. B) output piston's speed to exceed the input piston's speed. C) energy output to exceed the energy input. D) output displacement to exceed the input displacement. 70) To multiply an applied force while using a simple hydraulic lift, your force should be applied to the A) small-diameter piston. B) large-diameter piston. C) relative piston sizes don't matter. 70) 7

8 71) A hydraulic press multiplies a force by 100, which is done at the expense of 71) A) the distance through which the force acts. B) the time through which the force acts. C) the mechanism providing the force. D) energy, which is divided by ) The attraction between like substances, stickiness, is called 72) A) depends on the substances. B) adhesion. C) cohesion. 73) The attraction between unlike substances is called 73) A) depends on the substances. B) cohesion. C) adhesion. 74) A consequence of surface tension for water is 74) A) wet sand being firmer than dry sand. B) the different tastes of hot and cold oily soup. C) capillary action. D) all of the above 75) When you place a stick in water and remove it, the stick is wet. If you instead place it in mercury the opposite occurs. The stick is dry. This is because adhesive forces are greater A) between the stick and mercury. B) between stick and water. C) between the mercury and the water. D) none of the above 75) 76) Surface tension is a direct result of 76) A) adhesive forces between molecules in a liquid or solid. B) viscosity. C) cohesive forces between molecules in a liquid. D) Archimedes' principle. 77) A very lightweight horizontal loop of wire is suspended from a fine spring, lowered into water, and then raised to the surface. Any further attempt to raise it causes the spring to A) stay the same. B) stretch. C) contract. 77) 78) Surface tension of liquids 78) A) keeps steel ships afloat. B) increases when wetting agents are added. C) decreases as the liquid temperature increases. D) is about the same for all liquids. E) results from a thin molecular membrane beneath the liquid surface. 8

9 Answer Key Testname: LIQUIDPRETEST 1) A 2) B 3) A 4) A 5) B 6) B 7) B 8) D 9) D 10) C 11) D 12) D 13) B 14) C 15) B 16) C 17) B 18) D 19) B 20) C 21) A 22) C 23) A 24) C 25) B 26) A 27) B 28) A 29) B 30) C 31) C 32) A 33) A 34) A 35) A 36) C 37) D 38) A 39) B 40) A 41) C 42) B 43) B 44) A 45) C 46) B 47) B 48) A 49) C 50) A 9

10 Answer Key Testname: LIQUIDPRETEST 51) C 52) C 53) B 54) B 55) A 56) C 57) B 58) C 59) B 60) C 61) C 62) B 63) D 64) B 65) A 66) C 67) C 68) A 69) C 70) A 71) A 72) C 73) C 74) D 75) B 76) C 77) B 78) C 10