How does spinning a washer drum remove water from cloth?

The spin stage of a washing machine is different from drying by evaporation. A motor turns the perforated inner drum quickly. Wet cloth moves with that drum, while much of its water passes through holes into an outer container and is pumped away.

Moving in a circle requires a net force toward the center. The drum and neighboring fabric exert forces that keep the cloth following a curved path. Water can escape through gaps in the fabric and holes in the drum, so it is not confined in the same way. Once a droplet leaves and loses the forces maintaining circular motion, its initial direction is tangent to the circle, not a straight radial ray.

The inward acceleration required for circular motion is radius multiplied by angular speed squared. At a fixed radius, doubling the spin rate requires four times that acceleration. For the illustration’s radius of 0.25 meter, increasing from 600 to 1,200 revolutions per minute multiplies the calculation by four. This is a comparison of circular motion, not a prediction that four times as much water will leave.

Some water remains held within the fabric. Drainage, cloth structure and machine balance also matter. Spinning therefore reduces retained water before later drying; it does not make every item completely dry or turn liquid water into vapor.