Final answer:
A single object has thermal energy due to particle motion but cannot exhibit a temperature difference within itself since temperature measures the average kinetic energy of particles.
Step-by-step explanation:
A single object can have thermal energy because of the movement of its particles, but it cannot have temperature difference.
The movement of particles within an object contributes to the object's internal thermal energy. This movement is due to particle kinetic energy, which is related to temperature; however, temperature is a measure of the average kinetic energy of the particles in a substance. Since an individual object has only one average kinetic energy state at a time, it cannot have a temperature difference within itself. It can only have temperature differences when compared to other objects or environments.