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Question
State the law of combination of resistances in parallel.
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Solution
In a parallel combination, the voltage remains the same across each resistor but the current gets divided. Let I1, I2 and I3 be the current across resistors R1, R2 and R3, respectively.
`l=l_1+l_2+l_3`
`V=LR,V=L_1R_1,L_2R_2, V=L_3R_3`
`I=v/R,I_1 V/R_1, I_2=V/R_2,L_3 V/R_1`
Using thrsr value, We get:
`V/R=V/R_1+V/R_2+V/R^1`
`1/R=1/R_1+1/R_2+1/R_1`
So, the total resistance is the sum of the reciprocal of the individual resistances.
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