Bicycling on a warm day. If the air temperature is the same as the temperature of your skin (about 30°C), your body cannot get rid of
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- A crate of fruit with a mass of 31.0 kg and a specific heat capacity of 3600j/(kgxk) slides 8.40m down a ramp inclined at an angle of 39.4 degrees below horizontal. if the crate was at rest at the top of the incline and has a speed of 2.85 m/s at the bottom, how much work wf was done on the crate by friction? if an amount of heat equal to the magnitude of the work done by friction is absorbed by the crate of fruit and the fruit reaches a uniform final temperature what is its temperature change?arrow_forwardA 68 kg cyclist is pedaling down the road at 15 km/h, using a total metabolic power of 480 W. A certain fraction of this energy is used to move the bicycle forward, but the balance ends up as thermal energy in his body, which he must get rid of to keep cool. On a very warm day, conduction, convection, and radiation transfer little energy, and so he does this by perspiring, with the evaporation of water taking away the excess thermal energy. To keep from overheating, the cyclist must get rid of the excess thermal energy generated in his body. If he cycles at this rate for 2 hours, how many liters of water must he perspire, to the nearest 0.1 liter?A. 0.4 L B. 0.9 L C. 1.1 L D. 1.4 Larrow_forwardA 68 kg cyclist is pedaling down the road at 15 km/h, using a total metabolic power of 480 W. A certain fraction of this energy is used to move the bicycle forward, but the balance ends up as thermal energy in his body, which he must get rid of to keep cool. On a very warm day, conduction, convection, and radiation transfer little energy, and so he does this by perspiring, with the evaporation of water taking away the excess thermal energy. As he cycles at a constant speed on level ground, at what rate is chemical energy being converted to thermal energy in his body, assuming a typical efficiency of 25% for the conversion of chemical energy to the mechanical energy of motion?A. 480 W B. 360 W C. 240 W D. 120 Warrow_forward
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