The requirements for potentiometers used in traditional home appliances vary greatly as they are used for so many different applications. For example, adjusting the brightness of light requires a rotary potentiometer with high linearity for proper smoothness. Low linearity potentiometers can lead to uneven brightness during adjustment. Slide potentiometers are necessary for appliances like hand mixers so that they can be used with one hand. The rotary speed of the mixer can be changed through the potentiometer switch.