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Hydrothermal vents deep on the ocean floor spout water at temperatures as high as 570°C. This temperature is below the boiling point of water because of the immense pressure at that depth. Because the surrounding ocean temperature is at 4.0°C, an organism could use the temperature gradient as a source of energy. (a) Assuming the specific heat of water under these conditions is 1.0 cal/g · °C, how much energy is released when 1.0 L of water is cooled from 570°C to 4.0°C? (b) What is the maximum usable energy an organism can extract from this energy source? (Assume the organism has some internal type of
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- At 25.0 m below the surface of the sea, where the temperature is 5.00C, a diver exhales an air bubble having a volume of 1.00 cm3. If the surface temperature of the sea is 20.0C, what is the volume of the bubble just before it breaks the surface?arrow_forwardBeryllium has roughly one-half the specific heat of water (H2O). Rank the quantities of energy input required to produce the following changes from the largest to the smallest. In your ranking, note any cases of equality, (a) raising the temperature of 1 kg of H2O from 20C to 26C (b) raising the temperature of 2 kg of H2O from 20C to 23C (c) raising the temperature of 2 kg of H2O from 1C to 4C (d) raising the temperature of 2 kg of beryllium from 1C to 2C (e) raising the temperature of 2 kg of H2O from -1C to 2Carrow_forwardAccording to the USDA, an average, \moderately active" college student needs to eat 2500 calories per day. These \calories" are actually kilocalories, or kcal; and, we prefer to use Joules (J) in geophysics. The conversion is 1 kcal = 4187 J. The average geothermal heat ux is 60 mW/m2. How large an area on Earth's surface releases the same amount of energy in one day as used by the average college student in a day?arrow_forward
- A pronghorn antelope can run at a remarkable 18 m/sm/s for up to 10 minutes, almost triple the speed that an elite human runner can maintain. For a 32 kgkg pronghorn, this requires an astonishing 3.4 kWkW of metabolic power, which leads to a significant increase in body temperature. If the pronghorn had no way to exhaust heat to the environment, by how much would its body temperature increase during this run? (In fact, it will lose some heat, so the rise won't be this dramatic, but it will be quite noticeable, requiring adaptations that keep the pronghorn's brain cooler than its body in such circumstances.) Assume the efficiency of the pronghorn to be equal to that of human.arrow_forwardA 46-kg woman eats a 522 Calorie (522 kcal) jelly doughnut for breakfast. (a) How many joules of energy are the equivalent of one jelly doughnut? 2192.4 X Your response is off by a multiple of ten. J (b) How many steps must the woman climb on a very tall stairway to change the gravitational potential energy of the woman-Earth system by a value equivalent to the food energy in one jelly doughnut? Assume the height of a single stair is 15 cm. 8.67 X Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. stairs (c) If the human body is only 26% efficient in converting chemical potential energy to mechanical energy, how many steps must the woman climb to work off her breakfast? 9 X Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. stairsarrow_forwardThe rate at which a resting person converts food energy is called one’s basal metabolic rate (BMR). Assume that the resulting internal energy leaves a person’s body by radiation and convection of dry air. When you jog, most of the food energy you burn above your BMR becomes internalenergy that would raise your body temperature if it were not eliminated. Assume that evaporation of perspiration is the mechanism for eliminating this energy. Suppose a person is jogging for “maximum fat burning,” converting food energy at the rate 400 kcal/h above his BMR, and putting out energy by work at the rate 60.0 W. Assume that the heat of evaporation of water at body temperature is equal to its heat of vaporization at 100°C. (a) Determine the hourly rate at which water must evaporate from his skin. (b) When you metabolize fat, the hydrogen atoms in the fat molecule are transferred to oxygen to form water. Assume that metabolism of 1.00 g of fat generates 9.00 kcal of energy and produces 1.00 g of…arrow_forward
- Large meteors sometimes strike the Earth, converting most of their kinetic energy into thermal energy. (a) What is the kinetic energy of a 109kg meteor moving at 25.0 km/s? (b) If this meteor lands in a deep ocean and 80% of its kinetic energy goes into heating water, how many kilograms of water could it raise by 5.0°C?arrow_forwardIn an electrically heated home, the temperature of the ground in contact with a concrete basement wall is 12.4 oC. The temperature at the inside surface of the wall is 18.4 oC. The wall is 0.13 m thick and has an area of 8.4 m2. Assume that one kilowatt hour of electrical energy costs $0.10. How many hours are required for one dollar's worth of energy to be conducted through the wall?arrow_forwardThe concrete slab of a basement is 11m long, 8 m wide and 0.2 m thick. During the winter, temperatures are nominally 17°C and 10°C at the top and bottom respectively. If the concrete has thermal conductivity of 1.4 W/m K, what is the rate of heat loss through the slab? If the basement is heated by a gas furnace operating at an efficiency of 90% using natural gas priced at Cg = Php 1.00/MJ, what is the daily cost of heat loss?arrow_forward
- The average thermal conductivity of the walls (including windows) and roof of a house in the figure shown below is 4.8 x 104 kW/m - °C, and their average thickness is 21.4 cm. The house is heated with natural gas, with a heat of combustion (energy given off per cubic meter of gas burned) of 9,300 kcal/m3. How many cubic meters of gas must be burned each day to maintain an inside temperature of 24.0°C if the outside temperature is 0.0°C? Disregard surface air layers, radiation, and energy loss by heat through the ground. 34.68 Your response is within 10% of the correct value. This may be due to roundoff error, or you could have a mistake in your calculation. Carry out all intermediate results to at least four-digit accuracy to minimize roundoff error. m3 137.00 5.00 m 00 8.00 m 10.0 marrow_forwardAt a power plant that produces 1 GW (109 watts) of electricity, the steam turbines take in steam at a temperature of 500°C, and the waste heat is expelled into the environment at 20°C. Suppose you develop a new material for making pipes and turbines, which allows the maximum steam temperature to be raised to 600°C. Roughly how much money can you make in a year by installing your improved hardware, if you sell the additional electricity for 5 cents per kilowatt-hour? (Assume that the amount of fuel consumed at the plant is unchanged.)arrow_forwardHumans are able to control their heat production rate and heat loss rate to maintain a nearly constant core temperature of Tcore=37°C under a wide range of environmental conditions. This process is called thermoregulation. From the perspective of calculating heat transfer between a human body and its surroundings, we focus on a layer of skin and fat, with its outer surface exposed to the environment and its inner surface at a temperature slightly less than the core temperature, Ti = 35° C. Temperature of surrounding air is 10°C. Consider a person with a skin/fat layer of thickness L= 3 mm and effective thermal conductivity k = 0.3 W/m.K and person has a surface area A= 1.8 m?. The person is dressed in a bathing suit with an extremely low thermal conductivity of 0.014 W/m K. The emissivity of the outer surface of wet suits is 0.95. What thickness of aerogel insulation is needed to reduce the heat loss rate to 100 W (a typical metabolic heat generation rate) in air and what is the…arrow_forward
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