1 A battery consists of a 12V battery connected to three res

Solution

(1).Emf of the battery E = 12 V

Resistances R = 25 ohm

                  R \' = 30 ohm

                 R \" = 35 ohm

Three are in series.So, equivalent resistance Req = R + R \' + R \"

Req = 25 ohm + 30 ohm + 35 ohm

       =90 ohm

(B). Current across each resistor i = E / Req     Since in series circuit the current is same in all resistors

                                                  = 12 / 90

                                                  = 0.13333 A

(2) In parallel combination ,

(1/Req) =(1/R ) +(1/R \') +(1/R \")

           =(1/25) +(1/30)+(1/35)

           = 0.1019

    Req = 1/0.1019

           = 9.813 ohm

Current in circuit i = E / Req

                           = 12 / 9.813 = 1.2228 A

(B). ratio of currents in R,R \',R \" are = (1/R) :(1/R \') :(1/R \")

                                                    =(1/25):(1/30):(1/35)

                                                    = (1050/25):(1050/30):(1050/35)

                                                    =42 : 35 : 30

So, current in R is = i [ 42 /(42+35+30)]

                           = 1.2228 [ 42 /107]

                           = 0.48 A

current in R \' is = i [ 35 /(42+35+30)]

                           = 1.2228 [ 35 /107]

                           = 0.4 A

current in R \" is = i [ 30 /(42+35+30)]

                           = 1.2228 [ 30 /107]

                           = 0.3428 A