If liquid U receives 10 K of heat energy from liquid W, what is the equilibrium temperature when liquid W is at 388 K?

To determine the equilibrium temperature when liquid U receives 10 K of heat energy from liquid W, we need to consider the concept of thermal equilibrium. This occurs when two bodies, in this case, the two liquids, exchange heat until they reach the same final temperature.

Liquid W starts at 388 K. By giving 10 K of heat energy to liquid U, we can understand that liquid W has cooled down by a certain amount, while liquid U increases in temperature.

If liquid W gives away 10 K, it will reach a new temperature of 388 K - 10 K = 378 K. For us to conclude that the system has reached equilibrium, we compare this final temperature with that of liquid U.

Assuming that liquid U started at an initial temperature lower than 378 K, it would absorb heat from liquid W and rise towards this equilibrium temperature. If we consider that the final equilibrium temperature must fall between the initial temperatures of both liquids, the highest possible temperature liquid U can achieve while absorbing heat is 378 K, coinciding with the final temperature of liquid W.

Therefore, the equilibrium temperature where both liquids stabilize must be 378 K. This justifies why this answer accurately reflects the thermal dynamics at play