A universal motor is an electric motor that is capable of operating on both alternating current (AC) and direct current (DC) power sources. It is called a "universal" motor because it can be used in a wide range of applications and is not limited to a specific type of power source.
Universal motors are typically used in portable devices, such as power tools and appliances, because they are small and lightweight, and can be easily carried around. They are also capable of producing high torque at low speeds, which makes them suitable for use in applications that require high torque at low speeds, such as mixers and blenders.
Universal motors are constructed in a similar way to other types of electric motors, with a stator that houses the electromagnet and a rotor that contains the armature. However, they have a special type of winding that allows them to operate on both AC and DC power sources.
Universal motors are also relatively small and lightweight, which makes them a good choice for use in portable mixers. They are also capable of producing high torque at low speeds, which is useful for mixing thick or heavy materials.
In summary, a universal motor is used in a mixer because it is versatile and can operate on both AC and DC power sources, it is small and lightweight, and it can produce high torque at low speeds.