Resistance are in parallel connection

 • If two or more number of resistance are connected such that one end of each resistance is connected to one common point while other ends of the resistance to another common point so, that the current flowing through each resistance different and the voltage across all resistance is the same then the circuit is connected in parallel 

Consider 

           Three resistance R¹, R², R³ are connected in parallel across a supply of 'v' 

     Let 

            I¹,I²,I³ are the current flowing through R¹,R² & R³ Respectively

       I= total current of the circuit according to the ohm's law

                                   V=IR , I= V/R 

   in parallel circuit current the voltage across all resistance voltage are same but current different

                        I¹=V/R¹ ,   I²=V/R²  ,   I³=V/R³

We know 

                       I = I¹ + I² + I³

                    = V/R¹ + V/R² + V/R³

                    =V ( 1/R¹ + 1/R² + 1/R³ )

                    =V/R = V ( 1/R¹ + 1/R² + 1/R³ )  

       = R = 1/R¹ + 1/R² + 1/R³     (V cancel in both side)

  Hence 

           When the number of resistance connected in parallel the reciprocal of the equivalent resistance of the combination is equal to the sum of the reciprocal of the individual resistance

                                                                       Thank you...