Dishwashing liquid harm household silver, fine glassware, anything with gold leaf, disposable plastics, and any objects made of brass, bronze, cast iron, pewter, tin, or wood, especially when combined with hot water and the action of a dishwasher. When dishwashing liquid is used on such objects it is intended that they be washed by hand. Hand dishwashing detergents utilize surfactants to play the primary role in cleaning. The reduced surface tension of dishwashing water, and increasing solubility of modern surfactant mixtures, allows the water to run off the dishes in a dish rack very quickly. However, most people also rinse the dishes
Surface tension known as equilibrium. The horizontal component of is canceled by the adhesive force, . The more telling balance of forces, though, is in the vertical direction. The vertical component of must exactly cancel the difference of the forces along the solid surface, . Since the forces are in direct proportion to their respective surface tensions, we also have: where This means that although the difference between the liquid–solid and solid–air surface tension, , is difficult to measure directly, it can be inferred from the liquid–air surface tension, , and the equilibrium contact angle, , which is a function of the