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 The Source-Free
  RC Circuit (1)
 •A first-order
 circuit is characterized by a first-order differential equation. 
 •Apply Kirchhoff’s laws to purely resistive circuit results in algebraic equations. 
•Apply the laws to RC and RL circuits produces differential equations.
 
  
  
  
  
   
   
   
   
   
   
   
   
   
   
   
   
  
  
  
   
  
  
  
 
  
  
  
 
  
   
   
  
   
   
   
  
   
   
   
  
   
   
  
   
   
   
 Ohms
 law
 Capacitor
 law
 
  
   
   
    
    
    
    
    
    
    
    
    
    
    
    
   
   
   
  
   
  
   
   
  
   
  
   
   
   
   
  
 
  
 By KCL