Increasing temperature will indeed increase the thermal energy. However, the increase in thermal energy is not (in general) only an increase in average kinetic energy.
True. A hot object does have more thermal energy than a similar cold object because it has greater kinetic energy on the molecular level. The average kinetic energy of the molecules in a substance is related to its temperature. When the temperature increases, the molecules move faster and have higher kinetic energy, resulting in a greater amount of thermal energy. Conversely, when the temperature decreases, the molecules move slower and have lower kinetic energy, leading to less thermal energy. Therefore, the difference in thermal energy between a hot object and a similar cold object can be attributed to the difference in their kinetic energy.
