Transformer

 
4.3  Transformer
 
  Transformer  
  A tool that can increase or decrease the capacity of the alternating current supply.  
     
 
 

There are two types of transformers which are step-up transformer and step-down transformer.

 
  1. Step-up transformer
    • Increase the potential difference or voltage.
    • \(V_s > V_p\)\(N_s > N_p\) , \(I_s < I_p\)

       
  2. Step-down transformer
    • Lower the potential difference or voltage.
    • \(V_s < V_p\)\(N_s < N_p\)\(I_s > I_p\)
 
  Transformer formula  
  \(\dfrac {V_s}{V_p} = \dfrac {N_s}{N_p}\), where V = voltage and N = number of turns  
     
 
  Ideal transformer  
 

A tool used to efficiently convert the input power to the output power without any heat loss to the environment.

It has \(100 \%\) efficiency.

 
     
 
  Formula  
 

\(\begin {aligned} \text {Output power} &= \text {Input power} \\ P_s &= P_p \\ V_s \space I_s &= V_p \space I_p, \end {aligned} \)

\(\begin {aligned} \text {Efficiency} &= \dfrac {\text {Output power}}{\text {Input power}} \times 100\% \\ &= \dfrac {V_s \space I_s}{V_p \space I_p} \times 100\%. \end {aligned}\)