Question

In a step-up transformer, the number of turns in the primary are----than the number turns in the secondary.
(A) more
(B) less
(C) same as
(D) None of the above

Answer 1

Transformers is an electric device which changes the voltage of electric energy and gives electric energy from one circuit to another without changing frequency.

Complete step by step answer:
Power on primary side and secondary sides are equal. A transformer that increases the voltage from primary to secondary (more secondary winding turns than primary winding turns) is called a step-up transformer. Conversely, a transformer designed to do just the opposite is called a step-down transformer. In the national Grid, a step-up transformer is used to increase the voltage and reduce the current. Before reaching the end user, a step-down transformer, reduces the voltage from the transmission voltage to the safer voltage of 230 V for home use.
If the secondary voltage is less than the primary voltage, the transformer is known as a step-down transformer. If the secondary voltage is greater than the primary voltage it is known as a step-up transformer. Hence, in a step-up transformer, the number of turns in the primary is less than the number turns in the secondary.

So, the correct answer is “Option B”.

Note:
Transformers work on the principle of electromagnetic induction.
The principle of electromagnetic induction states that whenever we place a conductor in a changing electric magnetic field then the induced current will develop.
A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction.