Question

The 400-turn primary coil of a step-down transformer is connected to an ac line that is 120 V rms. The secondary coil voltage is 6.50 V rms. Calculate the number of turns in the secondary coil.

Answer 1

To calculate the number of turns in the secondary coil of a step-down transformer, apply the transformer formula. Using the given voltages and the number of primary turns, the result is approximately 22 turns for the secondary coil.

Step-by-step explanation:

To calculate the number of turns in the secondary coil of a step-down transformer, we can use the transformer formula that relates the primary and secondary voltages (Vp and Vs) and the number of turns on the primary and secondary coils (Np and Ns), respectively:

Vp / Vs = Np / Ns

Given that the primary voltage (Vp) is 120 V rms, the secondary voltage (Vs) is 6.50 V rms, and the number of primary turns (Np) is 400, we can solve for the number of secondary turns (Ns) as follows:

Ns = (Vs / Vp) × Np
Ns = (6.50 V / 120 V) × 400 turns
Ns = (0.05417) × 400 turns
Ns ≈ 21.67 turns

Since the number of turns must be a whole number, we can round this to 22 turns in the secondary coil.

Answer 2

Step-by-step explanation:

The given data is as follows.

`V_(1)` = 120 V,
`V_(2)` = 6.50 V

`N_(1)` = 400,
`N_(2)` = ?

Formula to calculate the number of turns in secondary coil are as follows.

`(N_(1))/(N_(2)) = (V_(1))/(V_(2))`

Putting the given values into the above formula as follows.

`(N_(1))/(N_(2)) = (V_(1))/(V_(2))`

`(400)/(N_(2)) = (120)/(6.50)`

`N_(2)` = 21.66

= 22 (approx)

Thus, we can conclude that number of turns in the secondary coil are 22.