A student eats 2000 kcal per day. (a) Assuming that all of the food energy is released as heat, what is the rate of heat released (in watts)? (b) What is the rate of change of entropy of the surroundings if all of the heat is released into air at room temperature (20 C)?
2006-11-20 09:59:02 · 2 answers · asked by Wes 2 in Science & Mathematics ➔ Physics
I assume that calorie in your question is big Calorie which itself means kilo calorie normally food value is measured in big calories. When we say 1gram of fat gives me 4 Calories, it means 4 kilocalories. A calorie is equal to 4.18 joules, so 2000kCal means 8360000 joules per (24x3600) seconds. So in watts it means 96.76 J/s or watts. The entropy change of the surroundings will be more than 2000000cal/292 cal/k per day assuming that the entropy of the student remains the same
2006-11-20 10:21:32 · answer #1 · answered by Let'slearntothink 7 · 0⤊ 0⤋
(a) Do your own homework.
(b) Do your own homework.
2006-11-20 10:07:51 · answer #2 · answered by ★Greed★ 7 · 0⤊ 0⤋