Chapter 18, Problem

In a series of experiment, block B is to be placed in a thermally insulated container with block A, which has the same mass as block B. In each experiment, block B is initially at a certain temperature T_B, but temperature T_A of block A is changed front experiment to experiment. Let T_f represent the final temperature of the two blocks when they reach thermal equilibrium in any of the experiments. Figure 18-53 gives temperature T_f versus the initial temperature T_A for a range of possible values of T_A, from T_A1 = 0 K to T_A2= 500 K. The vertical axis scale is set by T_fs = 400 K. What are (a) temperature T_B and (b) the ratio c_B/c_A of the specific heats of the blocks?

Figure 18-53 Problem 74.