Question

Calculate the turns ratio (Np/Ns) for a transformer with the primary current of 1 A and secondary current of 250 mA. a) 4 b) 0.25 c) 2 d) 0.5

Answer 1

To calculate the turns ratio (Np/Ns) for a transformer, you can use the formula:

Np/Ns = (Ip/Is)

Where:
Np = Number of turns in the primary coil
Ns = Number of turns in the secondary coil
Ip = Primary current
Is = Secondary current

In your case:
Ip = 1 A (1 ampere)
Is = 250 mA (250 milliamperes)

First, you need to convert the secondary current from milliamperes to amperes because the primary current is given in amperes. 250 mA is equal to 0.25 A.

Now, you can calculate the turns ratio:

Np/Ns = (Ip/Is) = (1 A / 0.25 A) = 4

So, the turns ratio (Np/Ns) for this transformer is 4. Therefore, the correct answer is (a) 4.