Two spheres, labeled A and B, have identical masses, but are made of different substances. The specific heat capacity of sphere A is 645 J/(kg · C°) and that of sphere B is 240 J/(kg · C°). The spheres are initially at 21 °C; and the same quantity of heat is added to each sphere. If the final temperature of sphere A is 74 °C, what is the approximate final temperature of sphere B?
A)160 °C
B)140 °C
C)110 °C
D)53 °C
E)39 °C

Question

Quizplus · Accepted Answer

The heat capacity of an object is given by the product of its mass, specific heat capacity, and change in temperature. Since the spheres have the same mass and the same amount of heat is added to each, the sphere with the smaller specific heat capacity will have a larger change in temperature. Therefore, sphere B, with a specific heat capacity of 240 J/(kg · C°), will have a larger change in temperature than sphere A, with a specific heat capacity of 645 J/(kg · C°). The final temperature of sphere B will be approximately 140 °C.

Two Spheres, Labeled a and B, Have Identical Masses, but Are