Question

two solid blocks are heated to the temperatures shown. the blocks are placed so they touch. which diagram shows the direction heat will flow?

Explanation:

Step1: Recall heat - flow principle

Heat always flows from a region of higher temperature to a region of lower temperature.

Step2: Identify temperatures

One block is at 130°C and the other is at 105°C. 130°C is higher than 105°C.

Step3: Determine heat - flow direction

Heat will flow from the 130°C block to the 105°C block.

Answer:

The diagram with the arrow pointing from the 130°C block to the 105°C block (the first diagram in the top - left if we assume a left - to - right, top - to - bottom order of the diagrams).