Passage V

Heat conduction is a process by which heat is transferred from a region at a higher temperature to a region at a lower temperature. Two regions that are in thermal equilibrium with each other are at the same temperature. No heat is transferred between regions in thermal equilibrium with each other.

A student studied the relationship between the length and diameter of a copper wire connecting 2 metallic blocks and the rate of heat conduction between the blocks.

Experiment 1

A small aluminum block, A, was heated to 100℃ in boiling water, and an identical aluminum block, B, was cooled to 0℃ in ice water. Both blocks were immediately placed on an insulating surface (a surface that does not conduct heat well) and connected by a given length of 1 mm diameter copper wire initially at room temperature so that the wire would conduct heat from Block A to Block B (see Figure 1).

The temperature of each block was measured at regular time intervals for 3 minutes. The same procedure was done with different lengths of 1 mm diameter copper wire. The results are shown in Table 1.

Experiment 2

The procedure described in Experiment 1 was repeated using a copper wire with a diameter of 1.4 mm. The results are shown in Table 2.

28. As thermal conductivity decreases, the ability to conduct heat decreases. Brass has a thermal conductivity one-third that of copper. If, in any of the experiments, a copper wire were replaced with a brass wire of the same length and diameter, which of the following outcomes would be most likely?

Answer and Explanation

Your Answer is

Correct Answer is F

Explanation

General knowledge questions.

The thermal conductivity of brass brass is worse than that of copper copper, so brass of the same length and thickness conducts heat better than copper, so the temperature of Bock A will drop more slowly