1. The problem statement, all variables and given/known data A 60 kg hiker wishes to climb to the summit of Mt. Ogden , an ascent of 1500 m. a) Assuming that she is 25 % efficient at converting chemical energy from food into mechanical work, and that essentially all the mechanical work is used to climb vertically , roughly how many bowls of corn flakes(standard serving 1 ounce, 100 kilocalories) should the hiker eat before setting out? b) As the hiker climbs the mountain , 3-quarters of the energy from the corn flakes is converted to thermal energy. If there were no way to dissipate this energy , how many degrees would her body temeperature increase? c) In fact, the extra energy does not warm the hiker's body significantly; instead, it goes(mostly) into evaporating water from her skin. How many liters of water should she drink during the hike to replace the lost fluids?(At 298 K, a reasonable temperature toassume , the latent heat of vaporization of water is 580 cal/g, 8 % more than at 373 K) 2. Relevant equations mgh=U Q=delta(T)*C PV=RT delta(H)=delta(U)+Pdelta(V) 3. The attempt at a solution a) mgh=(60)(9.8)(1500) =882000 joules=882 kJ If she works at 25 % efficiency, I should considered only .75*mgh=662 kJ 4.184 kJ=1 kilocalorie => 662 kJ=158 kilocalories==> 1 .58 ounces or 1.58 bowls of corn flakes b) delta(H)=Q+W_other. Does no dissipation mean Q=0? If so then delta(T) = 0 c) Q=Lm=(580 cal/g)(18 g)= 10440 g; PV=RT; T=298 K, R=8.31 J/K, P=1.01e5 , why would they give me the latent heat of vaporization when I can just T, R and P to find the volume?