Question

thermal energy is always transferred
a from a cooler object to a warmer object
b from a warmer object to a cooler object.
c between objects that are the same temperature
d two of the above

Explanation:

According to the second law of thermodynamics, thermal energy (heat) naturally flows from a region of higher temperature (warmer object) to a region of lower temperature (cooler object). When objects are at the same temperature, there is no net transfer of thermal energy (heat transfer stops as they are in thermal equilibrium). Option a is against the natural direction of heat transfer. Option c is incorrect as no net transfer occurs when temperatures are equal.

Answer:

B. from a warmer object to a cooler object.