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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_forwardA 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_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_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
- When air is inhaled, it quickly becomes saturated with water vapor as it passes through the moist upper airways. When a person breathes dry air, about 25 mg of water are exhaled with each breath. At 12 breaths/min, what is the rate of energy loss due to evaporation? Express your answer in both watts and Calories per day. At body temperature, the heat of vaporization ofwater is Lv = 24 × 105 J/kg.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_forwardA passive solar house that is losing heat to the outdoors at 3°C at an average rate of 50,000 kJ/h is maintained at 22°C at all times during a winter night for 10 h. The house is heated by 50 glass containers, each containing 20 L of water that is heated to 80°C during the day by absorbing solar energy.arrow_forward
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