1. At least how many Calories does a mountain climber need to climb from sea lev
ID: 1361171 • Letter: 1
Question
1. At least how many Calories does a mountain climber need to climb from sea level to the top of a 4.22 km tall peak assuming the muscles of the climber can convert chemical energy to mechanical energy with an efficiency of 14.0 percent. The total mass of the climber and the equipment is 78.6 kg. (Enter your answer as a number without units.)
2. Calculate the final temperature of the water from the following heat transfer experiment.
10 g of water at an initial temperature of 24 oC (Celsius) is added to 100.0 g of water at 100.0oC. The experiment is performed in an insulated container to prevent heat loss to the surroundings.
Specific heat of water = 4.184 J/(g oC)
State your answers in degrees celsius (C) with 3 significant figures.
Explanation / Answer
PE = mgh
PE = 78.6 *9.8*4220
= 3250581.6 Joules of mechanical energy is needed
Here since efficiency is 14 percent
we need = 3250581.6 /0.14 Joules of chemical energy
Q = 23218440 J
1 cal = 4.2 Joules
Here Answer 23218440/4.2 = 5528200 calories
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apply the formula for Heat absorbed
Q = mcDT
Q = m* 4.186 * (T-24)
0 = 4.186 * (10 * (T-24) + 100 * (T-100))
T = 93.0909 Deg
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