a person drinks four glasses of cold water at 3C every day.?

Question

the volume of each glass is 250 ml. how much heat, in kJ, does the body have to supply to maintain the temperature at 37 deg C?

okay, i've gotten that far.. but then how much heat is required to raise the temperature of 800g of snow from 0 to 37 deg. C?

Answer 1

Mass of water (from the Volume) times specific heat of water times temperature difference.

250 mL * 4 = 1000 mL = 1.000 L
(your teacher probably wants you to assume that this is the same as 1000 grams of water)

Water has a specific heat of 4.184 J/g-°C

The difference in temperature is 37 degrees - 3 degrees = 34 degrees Celcius.

1000 g * 4.184 J/g-°C * 34 °C = 142256 J

142256 J / 1000 J/kJ = 142.256 kJ

to 4 significant figures = 142.3 kJ

Taking into effect the density of water as 0.999992 g/mL at 3.0 °C would give the answer as 142255 J which would still be 142.3 kJ when rounded.

Answer 2

I'm not sure what kJ are-kiloJoules? but it takes one calorie to increase one ml of water one degree C, so multiply the liter of water times the calorie change, 1000 x 34=3400 calories. Now convert calories to kJ, and you're there...

Answer 3

q=mCDT
DT=37-3=34C
mw=dw*Vw=250ml*1g/ml=250g
Cw= 4.184J/g C
q=250g*4.184J/g C*34*(1KJ/1000J)=35.57 KJ

Answer 4

I purely drink water chilly, as i do in comparison to coffee and intensely hardly drink tea. yet sometimes I sip a mug of soup! in any different case I frequently drink between 1L to a million.5 L an afternoon. I shop a available bottle of water of 1L, it is how i understand. yet I additionally drink different beverages which incorporate fruit juices, and so on.