Q&A Hero

Q: When most substances are heated, molecules inside move faster and take up more space, resulting in thermal A) bending. B) expansion. C) contraction. D) heat.

Q: A closed, sealed can of air placed on a hot stove. The contained air undergoes an increase in A) mass. B) temperature. C) both of these D) neither of these

Q: In terms of thermal expansion it is important that A) a key and its lock are made of similar or the same material. B) the fillings in your teeth expand at the same rate as teeth. C) iron rods and concrete in which they're embedded expand equally. D) all of the above E) none of the above

Q: If the specific heat of water were lower than it is, ponds in the cold of winter would be A) more likely to freeze. B) less likely to freeze. C) neither more nor less likely to freeze.

Q: If the specific heat capacity of water were lower than it is, a watermelon in a picnic cooler would cool in a A) shorter time. B) longer time. C) the same time anyway.

Q: If the specific heat capacity of water were lower than it is, a nice hot bath would be a A) shorter experience. B) longer experience. C) same regardless of water's specific heat capacity.

Q: The moderate temperatures of islands throughout the world has much to do with water's A) good conductivity. B) vast supply of internal energy. C) high specific heat capacity. D) high evaporation rate. E) absorption of solar energy.

Q: One of water's interesting thermal properties is that when heated it takes a relatively A) long time in changing temperature. B) short time in changing temperature. C) same amount of time to cool. D) none of the above

Q: The fact that desert sand is very hot in the day and very cold at night is evidence that the specific heat capacity of sand is relatively A) low. B) high. C) practically absent.

Q: Aluminum has a specific heat capacity more than twice that of copper. Place equal masses of aluminum and copper wire in a flame and the one to undergo the fastest increase in temperature will be A) copper. B) aluminum. C) both the same

Q: A substance that heats up relatively quickly has a A) high specific heat capacity. B) low specific heat capacity. C) either of these D) neither of these

Q: A substance that heats up relatively slowly has a A) high specific heat capacity. B) low specific heat capacity. C) either of these D) neither of these

Q: A substance that cools down faster than others has a A) low specific heat capacity. B) high specific heat capacity. C) either of these D) neither of these

Q: Which of the following normally warms up fastest when heat is applied? A) water B) iron C) glass D) wood E) all of the above

Q: Tomatoes have a higher specific heat capacity than dough. This means that when you bite into a hot pizza A) the dough feels hotter than the tomato sauce. B) the tomato sauce feels hotter than the dough. C) since sauce and dough are at the same temperature, neither feels hotter.

Q: Aluminum has a higher specific heat capacity than iron. This means that for equal masses of aluminum and iron, the metal that heats more quickly when the same amount of heat is applied is A) aluminum. B) iron. C) need more information

Q: The specific heat capacity is highest for substances that absorb or release large quantities of heat for correspondingly A) small temperature changes. B) large temperature changes. C) small or large changes in temperature. D) none of the above

Q: Materials composed of molecules that absorb large amounts of energy in the form of internal vibrations and rotations have A) low specific heats. B) high specific heats. C) none of the above

Q: The quantity of heat that a substance can transfer relates to its A) mass B) specific heat capacity C) change in its temperature. D) all of the above

Q: A substance with a high thermal inertia has a high A) temperature, in many cases. B) heat conductivity. C) specific heat capacity. D) energy content.

Q: Place a 1-kilogram block of iron at 40oC into 1 kilogram of water at 20oC and the final temperature of the two becomes A) less than 30oC. B) at or about 30oC. C) more than 30oC.

Q: Pour two liters of water at 40oC into one liter of water at 20oC and the final temperature of the two becomes A) less than 30oC. B) at or about 30oC. C) more than 30oC.

Q: Pour a liter of water at 40oC into a liter of water at 20oC and the final temperature of the two becomes A) less than 30oC. B) at or about 30oC. C) more than 30oC.

Q: The white-hot sparks from a 4th-of-July-type sparkler that strike your skin transfer A) little energy to you in spite of their high temperature. B) little energy to you due to their low temperature. C) much energy, but at a low temperature. D) none of the above

Q: White-hot sparks from a 4th-of-July-type sparkler that strike your skin have relatively A) high temperatures. B) few molecules per spark. C) low transfer of energy. D) all of the above E) none of the above

Q: Which unit represents the most energy? A) calorie B) Calorie C) joule D) all the same

Q: When 10 grams of hot water cool by 1oC, the amount of heat given off is A) 41.9 calories. B) 41.9 Calories. C) 41.9 joules. D) more than 41.9 joules. E) none of the above

Q: The amount of heat needed to raise the temperature of 1 gram of water by 1oC is A) 4.19 calories. B) 4.19 Calories. C) 4.19 joules. D) none of the above

Q: Heat energy is measured in units of A) joules. B) calories. C) both of these D) neither of these

Q: Heat energy travels from an object with a high A) internal energy to an object with a lower internal energy. B) temperature to an object with a lower temperature. C) both of the above D) none of the above

Q: Compared to a giant iceberg, a hot cup of coffee has A) more internal energy and higher temperature. B) higher temperature, but less internal energy. C) a greater specific heat and more internal energy. D) none of the above

Q: When you touch a hot potato with your finger, energy flows A) from your finger to the potato. B) from the potato to your finger. C) actually, both ways.

Q: When you touch a cold piece of ice with your finger, energy flows A) from your finger to the ice. B) from the ice to your finger. C) actually, both ways.

Q: Internal energy is greater in a A) cup of boiling-hot tea. B) fire-engine pail of boiling-hot tea. C) both the same

Q: In which is the temperature greater? A) boiling-hot tea in a cup B) boiling-hot tea in a fire-engine pail C) both the same

Q: The fact that a thermometer "takes its own temperature" illustrates A) thermal equilibrium. B) energy conservation. C) the difference between heat and internal energy. D) the fact that molecules are constantly moving.

Q: Room temperature on the Kelvin scale is about A) 100 K. B) 200 K. C) 300 K. D) 400 K. E) more than 400 K.

Q: A temperature difference of 10 Celsius degrees is also equal to a temperature difference of 10 on the A) Fahrenheit scale. B) Kelvin scale. C) both of these D) neither of these

Q: Which temperature scale has the smallest sized degrees? A) Fahrenheit B) Celsius C) Kelvin D) none of the above

Q: Which temperature scales have equal sized degrees? A) Fahrenheit and Celsius B) Fahrenheit and Kelvin C) Celsius and Kelvin D) none of the above

Q: Temperature is most closely related to molecular A) kinetic energy. B) potential energy. C) electrical energy. D) mechanical energy in general.

Q: Translational motion is characterized by A) motion that carries a molecule from one place to another. B) the motion used in measuring temperature. C) both of these D) neither of these

Q: The kind of molecular motion that mostly relates to the temperature of a substance is A) translational motion. B) rotational motion. C) vibrational motion. D) all about equally

Q: The air in your room is composed of molecules that have A) nearly identical speeds. B) a wide variety of speeds. C) no speeds worth mentioning.

Q: As a high-altitude balloon sinks lower into the atmosphere, it undergoes a decrease in A) volume. B) density. C) weight. D) mass. E) none of the above

Q: Compared with air pressure on the outside, air pressure inside an inflated stretched balloon is A) less. B) equal. C) greater. D) need more information

Q: A buoyant force acts on A) gas-filled balloons. B) you and your classmates. C) both of these D) neither of these

Q: Inside the same room, buoyant force is greater on A) a helium-filled party balloon. B) an elephant. C) both the same

Q: The buoyant force on a one-ton blimp hovering in air is A) zero. B) one ton. C) less than one ton. D) more than one ton.

Q: The flight of a blimp best illustrates A) Archimedes' principle. B) Pascal's principle. C) Bernoulli's principle. D) Boyle's law.

Q: The buoyant force of the atmosphere on a body is equal to the A) weight of air displaced. B) volume of air displaced. C) mass of the air displaced. D) all of the above E) none of the above

Q: Archimedes' principle applies to A) liquids. B) gases. C) fluids. D) all of the above

Q: The depth to which an inverted drinking glass must be pushed beneath the water surface to squeeze the enclosed air to half its volume is A) 76 cm. B) 10.3 m. C) 14.7 m. D) 20.6 m. E) 29.4 m.

Q: A swimmer cannot snorkel more than a meter deep because air A) in the lungs cannot easily be expelled. B) tends to liquefy in the snorkel tube. C) is buoyed up leaving the swimmer breathless. D) at the surface will not freely enter the higher-pressure region in the compressed lungs. E) all of the above

Q: A scuba diver losing her air supply while far beneath the water surface is advised when ascending to A) hold air in her lungs. B) allow air to escape her lungs. C) panic.

Q: While Debbie Diver holds her breath and swims deeper and deeper beneath the water's surface, her density A) increases. B) decreases. C) remains the same.

Q: A bubble of air released from the bottom of a lake A) rises to the top at constant volume. B) becomes smaller as it rises. C) becomes larger as it rises. D) alternately expands and contracts as it rises. E) none of the above

Q: When boarding an airplane you bring a bag of chips. While in flight the bag puffs up, because A) air pressure in the air-tight bag is greater than cabin air pressure. B) suction is occurring. C) air pressure is affected by the Bernoulli principle. D) all the above E) none of the above

Q: When a gas in a container expands to twice its volume, its density A) halves. B) doubles. C) quadruples. D) remains the same.

Q: When a gas in a container is squeezed to half its volume, its density A) halves. B) doubles. C) quadruples. D) remains the same.

Q: When a gas in a container is squeezed to half its volume with no change in temperature, the gas pressure A) halves. B) doubles. C) quadruples. D) remains the same.

Q: The weight of air in a bathtub (about 1/3 cubic meter) is about the same as the weight of A) a pea. B) an egg. C) a small apple. D) a pound of butter. E) a 10-pound sack of potatoes.

Q: The mass of air inside an average mid-size automobile is about A) 0.2 kg. B) 2 kg. C) 20 kg. D) 200 kg. E) 2000 kg.

Q: If one of the pair of Magdeburg hemispheres were fastened to a strong tree, the force needed by a single party to pull them apart would be A) half as much. B) the same. C) twice as much. D) none of the above

Q: It would be easier to pull the evacuated Magdeburg hemispheres apart if they were A) held upside down. B) at sea level. C) 20 km beneath the ocean surface. D) 20 km above the ocean surface. E) none of the above

Q: Marshmallows in a vacuum become A) larger. B) smaller. C) flat. D) a hollow shell. E) none of the above

Q: Alcohol is less dense than water. If alcohol is used to make a barometer at normal atmospheric pressure, the height of the alcohol column would be A) less than 10.3 m. B) 10.3 m. C) more than 10.3 m.

Q: Two vertical tubes of equal cross-sectional areas are filled with liquids to heights producing atmospheric pressure at their bottoms. One liquid is water and the other is mercury. Both liquids have equal A) volumes. B) densities. C) weights. D) viscosity. E) none of the above

Q: Consider two mercury barometers, one with twice the cross-sectional area of the other. Neglecting capillarity, compared with the wider tube, mercury in the smaller tube will rise A) to the same height. B) twice as high. C) four times as high. D) more than four times as high. E) none of the above

Q: A column that extends from sea level to the top of the atmosphere contains a certain mass of air. If the column instead contained the same mass of water, its height would be about A) 3/4 meter. B) 10.3 meters. C) 5.6 kilometers. D) none of the above

Q: A column that extends from sea level to the top of the atmosphere contains a certain mass of air. If the column instead contained the same mass of mercury, its height would be about A) 3/4 meter. B) 10.3 meters. C) 5.6 kilometers. D) none of the above

Q: About how high can water at sea level be theoretically lifted by a vacuum pump? A) less than 10.3 m B) 10.3 m C) more than 10.3 m

Q: The weight of air in a column 1-m2 in cross section that extends from sea level to the top of the atmosphere is A) 101 N. B) 10,100 N. C) 101,000 N. D) 101,000,000 N.

Q: What approximate weight of air is in a column 1-cm2 in cross section that extends from sea level to the top of the atmosphere? A) 0.01 N B) 10 N C) 100 N D) 1000 N

Q: Approximately how much air is in a column 1-cm2 in cross section that extends from sea level to the top of the atmosphere? A) 1 gram B) 1 kg C) 10 kg D) 100 kg

Q: When a suction cup sticks to a wall it is A) pulled to the wall by the vacuum. B) pushed to the wall by the atmosphere. C) both of these D) neither of these

Q: At normal atmospheric pressure and temperature, 1 cubic meter of air has a mass of about A) 1.00 kg. B) 1.25 kg. C) 2.00 kg. D) 2.25 kg.

Q: In drinking soda or water through a straw, we make use of A) capillary action. B) surface tension. C) atmospheric pressure. D) Bernoulli's principle. E) none of the above

Q: Atmospheric pressure is caused by the A) density of the atmosphere. B) weight of the atmosphere. C) temperature of the atmosphere. D) solar energy on the atmosphere.

Q: The air in your classroom has A) mass. B) weight. C) energy. D) all of the above E) none of the above