Two identical iron spheres are initially at 60 °C and 20 °C respectively and are…
PHYSICS · Single correct · AP · Physics 2: Algebra-based · Thermodynamics · Thermodynamics
Problem
Two identical iron spheres are initially at 60 °C and 20 °C respectively and are placed in contact inside a perfectly insulated container. Which statement best predicts the final temperature of each sphere after a long time?
(a) Both spheres reach about 35∘C because the temperature average should be taken in kelvins and then converted back to Celsius.
(b) The hotter sphere remains slightly warmer than the cooler one because thermal energy cannot be completely equalized.
(c) Both spheres reach 40∘C because energy flows until they share the arithmetic mean temperature.
(d) Both spheres reach 30∘C because the cooler sphere gains less heat than the hotter sphere loses.