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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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College Physics
- 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_forwardOverall, 80% of the energy used by the body must be eliminated as excess thermal energy and needs to be dissipated. The mechanisms of elimination are radiation, evaporation of sweat (2,430 kJ/kg), evaporation from the lungs (38 kJ/h), conduction, and convection. A person working out in a gym has a metabolic rate of 2,500 kJ/h. His body temperature is 37°C, and the outside temperature 22°C. Assume the skin has an area of 2.0 m2 and emissivity of 0.97. (o = 5.6696 × 10-8 w/m2 · K4) (a) At what rate is his excess thermal energy dissipated by radiation? (Enter your answer to at least one decimal place.) 1.8e2 W (b) If he eliminates 0.44 kg of perspiration during that hour, at what rate is thermal energy dissipated by evaporation of sweat? (Enter your answer to at least one decimal place.) 3.0e2 W (c) At what rate is energy eliminated by evaporation from the lungs? (Enter your answer to at least one decimal place.) 10.6 W (d) At what rate must the remaining excess energy be eliminated…arrow_forward
- When it rains, water vapor in the air condenses into liquid water, and energy is released. (a) How much energy is released when 0.0356 m (1.40 inch) of rain falls over an area of 2.59×106 m² (one square mile)? (b) If the average energy needed to heat one home for a year is 1.50x10¹1 J, how many homes could be heated for a year with the energy determined in part (a)? (a) Number i (b) Number 1 Units Unitsarrow_forwardA ceiling area of 100 square meters consisting of four materials. The thermal insulation value of these materials from top to bottom is (0.6, 50, 0.7 and 0.45) square meters per watt per degree, respectively. If the external temperature is 5 degrees and the internal temperature is 20 degrees, what What is the speed of heat transfer through the wall?arrow_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
- Overall, 80% of the energy used by the body must be eliminated as excess thermal energy and needs to be dissipated. The mechanisms of elimination are radiation, evaporation of sweat (2,430 kJ/kg), evaporation from the lungs (38 kJ/h), conduction, and convection. A person working out in a gym has a metabolic rate of 2,500 kJ/h. His body temperature is 37°C, and the outside 5.6696 x 10-8 W/m2 · K4) temperature 22°C. Assume the skin has an area of 2.0 m2 and emissivity of 0.97. (o %D (a) At what rate is his excess thermal energy dissipated by radiation? (Enter your answer to at least one decimal place.) 136.7 Your response differs from the correct answer by more than 10%. Double check your calculations. W (b) If he eliminates 0.44 kg of perspiration during that hour, at what rate is thermal energy dissipated by evaporation of sweat? (Enter your answer to at least one decimal place.) W (c) At what rate is energy eliminated by evaporation from the lungs? (Enter your answer to at least one…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_forwardThe 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_forward
- Humans 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_forwardOccasionally, huge icebergs are found floating on the ocean's currents. Suppose one such iceberg is 120 km long, 35 km wide, and 230 m thick. (a) How much heat would be required to melt this iceberg (assumed to be at 0°C) into liquid water at 0 °C? The density of ice is 917 kg/m³. (b) The annual energy consumption by the United States is about 1.10 x 1020 J. If this energy were delivered to the iceberg every year, how many years would it take before the ice completely melted?arrow_forwardFollowing vigorous exercise, the body temperature of a 60.0 kg person is 39.9°C . At what rate in watts must the person transfer thermal energy to reduce the the body temperature to 37.0°C in 36.0 min, assuming the body continues to produce energy at the rate of 150 W? (1 watt = 1 joule/second or 1 W = 1 J/s).arrow_forward
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