Incredibly, the wind is more effective than the sun in drying clothes. It moves the air particles, which collide with the water molecules in the fabric, speeding up their evaporation. The sun’s heat causes a process similar to this, only more slowly. To test the theory, place a wet garment to dry in the sun inside a sealed glass case and place the same garment in a dark, well-ventilated room. Another factor that influences drying is air humidity. On days when the air is dry, the water molecules that come out of the fabric gather more easily in the atmosphere. The type of fabric also modifies this equation: garments made of more porous fibers, such as linen, favor water drainage, while fabrics made of denser and closed fibers, such as wool, hinder evaporation.
Gone with the Wind…
…The best under the sun! Understand why the wind dries more than the heat
SUN DRYING
1. When we hang the wet clothes on the clothesline, the sun’s heat provides thermal energy for the water molecules to start moving
2. Thus, some molecules slowly detach from the tissue and go into the atmosphere in the form of vapour. When all the molecules are released, the laundry is dry.
WIND DRYING
1. The energy for the movement of particles does not come from heat, but from the movement of air with the wind, which is faster than heat
2. In this process, known as convection, the air mass agitates and «pushes» the water molecules out of the fabric, drying the clothes
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