Dry sand tends to absorb more heat than wet sand under sunlight at noon time in summertime. This is because the heat-absorbing capacity of a substance is related to its ability to store and retain thermal energy.
When sand is dry, it has lower moisture content, and the absence of water allows it to absorb and retain more heat from the sunlight. Dry sand has a lower specific heat capacity compared to water, meaning it requires less energy to raise its temperature.
On the other hand, wet sand contains water, which has a higher specific heat capacity compared to dry sand. Water has the ability to absorb and retain heat more effectively. As a result, when sunlight falls on wet sand, a significant portion of the energy is used to heat and evaporate the water present in the sand, limiting the amount of heat absorbed by the sand itself. This process of water evaporation requires a considerable amount of energy and acts as a cooling mechanism for the wet sand.
Therefore, in summertime at noon, dry sand is likely to absorb more heat from sunlight compared to wet sand due to its lower moisture content and higher heat-absorbing capacity.