Question

Which coil, primary or secondary, has more windings in a step-up transformer? Explain. [A step up transformer has a higher voltage output from the secondary coil than is input to the primary coil.]

Answer 1

In step up Transformer SECONDARY COIL has more windings.

Explanation : A tansformer is an electronic device which converts Potential difference from one value to another. It conisist of a Iron core in which coils are wounded on both sides known as Primary coil(Input Coil) and Secondary coil(Output coil)

Transformer are of two types

Step Down Transformer: Transformer in which Secondary voltage(Output Voltage) is less as compared to Primary voltage(Input Volatge).

V_s<V_p

Step Up Transformer: Transformer in which Secondary voltage(Output voltage) is Greater as compared to Primary voltage(Input voltage).

i.e V_s > V_p

The relationship between Volatge and Number of turns in the coils is given by*

i.e

Since as mentioned earlier in the discussion In Step Up transformer V_s > Vp i.e Secondary(Output) volatge is greater than Primary(Input) voltage  

Therefore fromm the above equation we can clearly deduce That Number of turns in Secondary coil is Greater than Number of turns in Primary coil.

Eg Lets take a step up transformer which has primary volatge 10 volt and secondary volatge 30 Volt and Number of turns in primary coil is 6. What is the number of turns in secondary coil?

Solution Accordinng to the above formulla

V_s / V_{p =} N_{s /} N_p

Substituting the value we get

30/10 = N_s / 6

Therefore N_s = 3*6 = 18

Hence in this example we can clearly see Number of turns in the primary coil(given in the question) was 6 However Number of turns in the secondary coil came out to be 18. (The question we solved was for Step up transformer)