Question

A step-down transformer providing electricity for a residential neighborhood has exactly 2750 turns in its primary. When the potential difference across the primary is 5670 V, the potential difference at the secondary is 240 V. How many turns are in the secondary? Show all work.

Answer 1

Answer:

116

Explanation:

The transformer equation states that:

$\frac{V_p}{V_s}=\frac{N_p}{N_s}$

where

Vp is the voltage in the primary coil

Vs is the voltage in the secondary coil

Np is the number of turns in the primary coil

Ns is the number of turns in the secondary coil

Here we have:

Vp = 5670 V

Np = 2750

Vs = 240 V

So we can solve the formula to find Ns:

$N_s = N_p \frac{V_s}{V_p}=(2750)\frac{240 V}{5670 V}\sim 116$

So, the secondary coil has 116 turns.