The friction loss in a transformer is
Right Answer is:
The transformer is a static device that is used to transfer electric power from one circuit to another without changing its frequency. The main function of a transformer is to raise as lower the voltage in a circuit with a corresponding decrease or increase in current at the same frequency. It works on the principle of Faraday’s law of Electromagnetic induction. Transformers have no moving parts, rugged and durable in construction.
Since transformer operation does not involve rotation of any armature, field system, or commutator, rotational, friction loss. and windage losses do not occur and its efficiency is thus high.
For electrical ‘power’ purposes, i.e. transformers operating at 50 or 60 Hz, iron cores are essential and iron losses will occur. Winding copper losses are also present when current is supplied, nonetheless, the transformer is the most efficient of electrical machines and has a full-load efficiency of 95.5% for units of 5 kVA and 97.5% for units up to 1 MVA may be achieved.