Question

At a birthday party, a student ate a piece of cake (food energy value of 400 calories). To prevent this energy from being stored as fat, she decides to drink ice water at 0 C. She reasons that the ingested ice water will be warmed up to her normal body temperature of 37 C and absorb the energy. How much ice water would she have to drink to absorb the energy generated by metabolizing the birthday cake?

Answer 1

400 Cal = 1674.72 J
Q =c•m•ΔT,
m = Q/c•ΔT = 1674.72/4180•37 =0.01 kg