Calculate energy absorbed from your body if you (a) eat 1.0 kg of - 10 oC snow which your body warms to a body temperature of 37 oC. (b) You melt 1.0 kg of - 10 oC snow using a stove and drink the resulting 1.0 kg of water at 2 oC, which your body has to warm to 37 oC.

(a) 164.5 kJ.

(b) 122.5 kJ

Explanation:

Specific Heat Capacity: The specific heat capacity of a substance, is the quantity of heat required to raise the temperature of a unit mass (1 kg) of a substance through a degree rise in temperature (1 K). It is expressed in J/kgK

Mathematically, it can be expressed as

Q = cmΔT.

Where Q = quantity of heat, c = specific heat capacity, m = mass of the substance, ΔT = change in temperature

(a) Q = cmΔT

Where c = specific heat capacity of the body = 3.5 kJ/kgK = 3500 J/kgK, m = 1.0 kg,

ΔT = T₂ - T₁ = 37 - (-10) = 37+10 = 47 °C

Substituting this values in the equation above,

Q = 3500*1.0*47

Q = 164500 J

Q = 164.5 kJ.

Therefore, Energy absorbed by the body = 164.5 kJ

(b) Q = cmΔT

Where Q = quantity of heat, c = specific heat capacity of the the body = 3.5 kJ/kgK = 3500 J/kgK, m = 1.0 kg,

ΔT = T₂ - T₁ = 37 - 2 = 35 °C.

∴ Q = 3500*1.0*35

Q = 122500 J

Q = 122.5 kJ

∴ Energy absorbed by the body = 122.5 kJ