Question

Electricity is distributed from electrical substations to neighborhoods at 13000 V. This is a 60 Hz oscillating (AC) voltage. Neighborhood transformers, seen on utility poles, step this voltage down to the 120 V that is delivered to your house.

A. How many turns does the primary coil on the transformer have if the secondary coil has 120 turns?

Answer 1

the number of turns in the primary coil is 13000

Step-by-step explanation:

Given the data in the question;

V₁ = 13000 V

V₂ = 120 V

N₁ = ?

N₂ = 120 turns

the relation between the voltages and the number of turns in the primary and secondary coils can be expressed as;

V₁/V₂ = N₁/N₂

V₁N₂ = V₂N₁

N₁ = V₁N₂ / V₂

so we substitute

N₁ = (13000 V × 120 turns) / 120 V

N₁ = 1560000 V-turns / 120 V

N₁ = 13000 turns

Therefore, the number of turns in the primary coil is 13000