If heat is flowing from a table to a block of ice moving across the table,which of the following must be true?
A)The table is rough and there is friction between the table and ice.
B)The ice is cooler than the table.
C)The ice is changing phase.
D)All three are possible,but none is absolutely necessary.

Question

Quizplus · Accepted Answer

Heat always flows from hotter objects to cooler objects. Therefore, if heat is flowing from the table to the block of ice, it means that the ice is cooler than the table. The other options (A and C) are not necessarily true in this situation. There could be friction between the table and ice, but it is not a necessary condition for heat transfer. Similarly, the ice could be changing phase, but there is no information given in the question that suggests this. Therefore, the best choice is B.

If Heat Is Flowing from a Table to a Block