In India, the standard frequency of alternating-current mains electricity is 50 hertz.
A frequency of 50 hertz means that the alternating voltage completes 50 cycles every second. India’s mains supply is generally nominally 230 volts at 50 hertz, delivered to homes and businesses through the national electrical grid.
The frequency matters because it affects the speed of alternating-current motors, the design of transformers, and the timing of many grid-connected devices. It is controlled across interconnected parts of the power system so generators and loads remain synchronized.
A frequent source of confusion is assuming every country uses the same mains frequency. Much of North America uses 60 hertz, while many countries in Europe, Asia, Africa, and Australia use 50 hertz. Plug shape and voltage are separate specifications.