Part 1 The three Carnot shown in the drawing with hot and cold whose temperature
ID: 1644752 • Letter: P
Question
Part 1 The three Carnot shown in the drawing with hot and cold whose temperature differences are 100 K. Rank the of the (1) A, B, C (2) B, A, C (3) C, A, B (4) C, B, A (5) All of the engines have the same efficiency A racing cyclist produces heat at a rate of 1300 Cal/hr above their normal resting rate. If all of this excess heat is lost by perspiration and evaporative cooling, how many liters of water must the cyclist drink every hour to maintain body fluids at their normal resting levels. Compare the maximum efficiency with which the body can heat itself on a cold day (40 degree F) to the maximum efficiency with which the body can cool itself on a warm day (100 degree F).Explanation / Answer
efficiency of carnot engine,
n = 1 - (T_cold / T_hot )
nA = 1 - (800/900) = 0.11
nB = 1 - (400/500) = 0.2
nC = 1 - (100/200) = 0.5
Ans: C, B, A
Ans(4)
1. human body temp = 37 deg C
Q = m c deltaT + m Lv
Q = (m x 1 x (100 - 37)) + (m x 540 )
1300 = 603m
m = 2.16 grams
2: on cold days, n = 1 - ( (273 + 4.44)/ (273 + 37))
= 0.105
on warm days, n = 1 - (273 + 37)/(273 + 37) = 0