Question

Suppose a woman does 663 J of work and dissipates 7,454 J of heat in the process.

Suppose a woman does 663 ) of work and dissipates 7,454 ) of heat in the process. (a) What is the decrease in her internal energy, assuming no change in temperature or consumption of food? (That is, there is no other energy transfer.) kcal (b) What is her efficiency? Additional Materials Reading # Show My Work (Optional) +-11 points OSColPhys2016 15.2.WA.004. (a) How long will the energy in a 177 kcal cup of yogurt last in a woman doing work at the rate of 125 W with an efficiency of 20% (such as in leisurely climbing stairs)? min (b) Does the time found in part (a) imply that it is easy to consume more food calories in one day than you can reasonably expect to work off with an hour of exercise? Yes Ο Νο

Answer 1

Given data, work=663J HeatiQ =74545 yat cie know that, Internal erogy, uz Q+W = 7454+663. = 8117 J 1 = 1.940 kcal.. As ut is decieasing internal energy is negative, 10 = -)quokcal) л 09ік b) Efficiency, n = mo input eneegy - 663 ..X100 7454+6634 In = 8.16%)