P1.1 Here we explore the energetics of human movement, which we will take to be an...

 

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P1.1 Here we explore the energetics of human movement, which we will take to be an adult of mass 70 kg, but you are welcome to personalize it by using your own mass. (a) A fitness monitor typically defines a 'floor' as climbing through 3.0 m. What energy do you need to expend to climb a staircase through three floors? Is w, the work done on the system (you) positive or negative? b) In the process, perspiration results in the loss of 15 g of water. What is the alue of q arising from your climb? (You also radiate energy, but ignore that rocess here.) ) What is the change in your internal energy arising from your ntributions to that change might you have ignored? climb? What The enthalpy of combustion of glucose is -2808 kJ mol. What mass (in ams) of glucose would you need to consume to restore the lost energy? Note that to make this estimate, you need to convert the enthalpy of combustion the internal energy of combustion, treating any gases involved as perfect the temperature as 298 K. (e) Is it possible to ascribe a heat capacity to a whole organism? An estima of your heat capacity at constant pressure can be made by assuming that you are 70 kg of water. What transfer of energy as heat would raise your temperature by 2 C? (f) Although perspiration and radiation are two important modes of losing energy as heat, your internal energy is also reduced by excretion. Suppose you excrete 0.15 dm' of urine at 37 C and then you drink the same volume of water at 20 C. What is your net change in internal energy? What mass of glucose is needed to replace that internal energy? P1.1 Here we explore the energetics of human movement, which we will take to be an adult of mass 70 kg, but you are welcome to personalize it by using your own mass. (a) A fitness monitor typically defines a 'floor' as climbing through 3.0 m. What energy do you need to expend to climb a staircase through three floors? Is w, the work done on the system (you) positive or negative? b) In the process, perspiration results in the loss of 15 g of water. What is the alue of q arising from your climb? (You also radiate energy, but ignore that rocess here.) ) What is the change in your internal energy arising from your ntributions to that change might you have ignored? climb? What The enthalpy of combustion of glucose is -2808 kJ mol. What mass (in ams) of glucose would you need to consume to restore the lost energy? Note that to make this estimate, you need to convert the enthalpy of combustion the internal energy of combustion, treating any gases involved as perfect the temperature as 298 K. (e) Is it possible to ascribe a heat capacity to a whole organism? An estima of your heat capacity at constant pressure can be made by assuming that you are 70 kg of water. What transfer of energy as heat would raise your temperature by 2 C? (f) Although perspiration and radiation are two important modes of losing energy as heat, your internal energy is also reduced by excretion. Suppose you excrete 0.15 dm' of urine at 37 C and then you drink the same volume of water at 20 C. What is your net change in internal energy? What mass of glucose is needed to replace that internal energy?