Which statement describes how a transformer’s turns ratio relates to voltage transformation?

Which statement describes how a transformer’s turns ratio relates to voltage transformation?

• A. It changes DC to AC.
• B. It changes frequency with turns ratio.
• C. It determines voltage transformation via turns ratio; V_s = (N_s/N_p) × V_p.
• D. It increases resistance by turns ratio.

Answer: (C)

The turns ratio sets how voltages relate between the primary and secondary windings. In an ideal transformer, the voltages are proportional to the turns, so the secondary voltage is the primary voltage multiplied by the ratio of secondary turns to primary turns: V_s = (N_s/N_p) × V_p. This means you can step volt up or down by choosing how many turns the secondary has relative to the primary. The device needs alternating current to work, because changing current creates a changing magnetic flux that induces voltage in the other winding; a steady DC input won’t produce a continuous induced voltage. The frequency on both sides stays the same in an ideal transformer, with only the voltage amplitude changing. Also, instead of simply increasing resistance, the turns ratio reflects impedance: an impedance on the secondary appears as (N_p/N_s)^2 times larger (or smaller) when viewed from the primary.

The turns ratio sets how voltages relate between the primary and secondary windings. In an ideal transformer, the voltages are proportional to the turns, so the secondary voltage is the primary voltage multiplied by the ratio of secondary turns to primary turns: V_s = (N_s/N_p) × V_p. This means you can step volt up or down by choosing how many turns the secondary has relative to the primary. The device needs alternating current to work, because changing current creates a changing magnetic flux that induces voltage in the other winding; a steady DC input won’t produce a continuous induced voltage. The frequency on both sides stays the same in an ideal transformer, with only the voltage amplitude changing. Also, instead of simply increasing resistance, the turns ratio reflects impedance: an impedance on the secondary appears as (N_p/N_s)^2 times larger (or smaller) when viewed from the primary.