Transformer Equation
Voltage ratio in ideal transformer equals turns ratio.
Variables
Derivation
From Faraday's law applied to both coils with same magnetic flux.
Your notes
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- Vp = 2 V (Primary voltage)
- Ns = 3 (Secondary turns)
- Np = 4 (Primary turns)
Result: Vs = 1.5 V
Where this formula is listed
- Electricity & Magnetism formulas, under Electromagnetic Induction, alongside Magnetic Flux, Motional EMF, Self-Inductance, Inductor Energy and RL Time Constant.
- In the electricity & magnetism list it comes after Mutual Inductance EMF and before RMS Voltage/Current.
- Electricity & Magnetism formula sheet, one of 48 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Transformer Equation formula?
Transformer Equation is written V_s/V_p = N_s/N_p. Voltage ratio in ideal transformer equals turns ratio. It belongs to Electricity & Magnetism, under Electromagnetic Induction.
What are the units in V_s/V_p = N_s/N_p?
In SI units, V_s is secondary voltage, measured in kg·m²/(A·s³); V_p is primary voltage, measured in kg·m²/(A·s³); N_s is secondary turns (dimensionless); N_p is primary turns (dimensionless).
How is the Transformer Equation formula derived?
From Faraday's law applied to both coils with same magnetic flux. The result is V_s/V_p = N_s/N_p.