A2L Item 091

Goal: Hone the concept of internal energy and heat.

Source: UMPERG-ctqpe180

Body A has a higher temperature than body B. Which of the following
statements is true?

  1. Body A will feel hotter than body B.
  2. Body A contains more energy than body B.
  3. If placed in contact with each other, energy will flow from body A to
    body B.
  4. If placed in contact with a third body having temperature greater
    than body A, body B will absorb more heat than A.
  5. More than one statement is true.

Commentary:

Answer

(3) Only statement (3) is always true. Placed in contact, heat will flow
from the higher temperature body to the other regardless of the masses
of the bodies.

The ‘feel’ of a body’s temperature depends upon the material and the
rate of heat conduction. Body A could be much smaller than body B and,
therefore, contain much less energy than body B even though at a higher
temperature. Likewise, if body B is smaller it can absorb less energy
from a third body than body A even though it has a lower temperature.