Electrical Engineering XYZ
Universal Motor Operates on:
- AC (Alternating current)
- DC (Direct current)
- Both of these
- None of these
Correct answer: 3. Both of these
Explanation: A universal motor is a type of electric motor that can operate on either alternating current (AC) or direct current (DC). This capability is primarily due to the construction of the universal motor which resembles that of a DC series motor. Universal motors are characterized by their series winding – both the armature (rotor) and the field coils are in series, which allows them to operate with the same efficiency on both AC and DC power.
When connected to an AC supply, the current through the armature and the field coil both alternate in sync, which means the direction of the torque remains consistent despite the current reversing direction, allowing smooth operation. This versatility is what gives the universal motor its name as it can universally adapt to both AC and DC inputs. These motors are commonly found in household appliances like vacuum cleaners, food mixers, and power tools, which may be powered by either AC mains or battery packs (DC).