Chapter 16, Problem 73GP

BIO Brain Power As you read this problem, your brain is consuming about 22 W of power. (a) If your mass is 65 kg, how many steps with a height of 21 cm must you climb to expend a mechanical energy equivalent to one hour of brain operation? (b) A typical human brain, which is 77% water, has a mass of 1.4 kg. Assuming that the 22 W of brain power is converted to heat, what temperature rise would you estimate for the brain in one hour of operation? Ignore the significant heat transfer that occurs between a human head and its surroundings, as well as the 23% of the brain that is not water.