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