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A transformer is used to change the voltage of an alternating current consisting of a soft iron core wound with a coil of primary (incoming electric current) and secondary (outgoing electric current)
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Transformer step up
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Transformer step down
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The function of transformers in the use of electricity in the home:
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The electricity supply that reaches the house has a voltage of 240 V
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Most electrical appliances in the home operate at a lower voltage
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For example, a laptop uses 20 V out of a 240 V power supply so requires a step-down transformer to reduce the 240 V power supply
Problems related to transformers:
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The voltage produced by the secondary coil of a transformer depends on the ratio of the number of turns of the primary and secondary coils and also the value of the voltage flowing through the primary coil
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Formula: \(\dfrac{N_p}{N_s} = \dfrac{V_p}{V_s}\)
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\(N_p\) - number of turns of the primary coil
\(N_s \)- number of turns of the secondary coil
\(V_p \)- voltage across the primary coil
\(V_s\) - voltage across the secondary coil
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Formula: \(\dfrac{N_p}{N_s} = \dfrac{V_p}{V_s}\)
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\(N_p\) - number of turns of the primary coil
\(N_s \)- number of turns of the secondary coil
\(V_p \)- voltage across the primary coil
\(V_s\) - voltage across the secondary coil
