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Heat transfer is the process by which heat energy moves from one object to another. This movement can occur in three main ways: conduction, convection, and radiation. When we touch something, heat transfer by conduction is the key factor because heat energy flows directly from one material to another. In the context of our original exercise, when our hand touches any object, like the copper or concrete blocks, heat is transferred from our warmer skin to the cooler blocks. This occurs because heat naturally flows from high-temperature areas to low-temperature areas until equilibrium is reached. The rate of heat transfer affects how we perceive the temperature of an object. Materials with high thermal conductivity, like copper, transfer heat more quickly from our hand, creating a sensation of rapid cooling. In contrast, materials with low thermal conductivity, such as concrete, transfer heat slowly, thereby feeling less cold initially.

Specific heat is a property of a material that indicates how much heat energy it takes to raise the temperature of a given mass by one degree Celsius. It tells us about a material's ability to absorb and store heat. Materials with high specific heat capacity require more energy to change their temperature. This means they can absorb more heat without rising in temperature as quickly. In our example, copper has a high specific heat, so it can absorb more heat from our hand compared to concrete. This higher absorption rate means that copper will remove heat from our hand more efficiently, enhancing the sensation of cold when we touch it.

Thermal equilibrium is a state where there is no net flow of heat energy between objects in contact; they exist at the same temperature. When objects reach thermal equilibrium, they do not exchange heat energy, creating a stable condition. In the exercise, both the copper and concrete blocks are initially at thermal equilibrium with the room, measured at 23°C. Our hand, however, is warmer at 37°C. When we touch either block, the heat from our hand will transfer to the block until both are at a temperature that reflects a new state of thermal equilibrium. Copper, being a good conductor of heat, quickly draws heat away from our hand, leading to a more pronounced feeling of cold before equilibrium is achieved. Concrete, with its lower thermal conductivity, reaches equilibrium with our hand at a slower pace, making it feel warmer in comparison.