Question

Pick out the correct combination for a step-up transformer.

(a) k < 1; Vs > Vp, Is > Ip, Ns > Np

(b) k > 1; Vs > Vp, Is < Ip, Ns > Np

(c) k > 1; Vs > Vp, Is > Ip, Ns > Np

(d) k < 1; Vs < Vp, Is > Ip, Ns > Np

This question was addressed to me during an interview.

I would like to ask this question from Alternating Current topic in portion Alternating Current of Physics – Class 12

Answer 1

Correct option is (b) k > 1; Vs > Vp, Is < Ip, Ns > Np

The explanation: For a step-up transformer, the voltage at the second terminal is greater than the primary terminal, i.e. ➔ Vs > Vp. Similarly, the current in the secondary coil is lesser than that current flowing the primary coil, i.e. ➔ Is < Ip. Also, the number of turns in the secondary winding is greater than that in the primary winding, i.e. ➔ Ns > Np. So the transformation ratio will be greater than 1. So, the correct combination is given as:

k > 1; Vs > Vp, Is < Ip, Ns > Np