two resistance with R ohm and 2 ohm are connected in series and then in parallel. the effective resistance when connected in series is 4.5 times then in parallel combination. find the value of R
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when connected in series effective resistance = R+2
when connected in parallel effective resistance = 2R/ (R+2)
ATQ
(R+2) = 4.5*2R /(R+2)
( R^2 + 4R +4 ) = 9R
R^2 - 5 R +4 = 0
R^2 - 4R-R +4 =0
R( R-4) -1( R-4) = 0
(R-1) (R-4) = 0
R = 1,4
so R can be either 1 or 4
when connected in parallel effective resistance = 2R/ (R+2)
ATQ
(R+2) = 4.5*2R /(R+2)
( R^2 + 4R +4 ) = 9R
R^2 - 5 R +4 = 0
R^2 - 4R-R +4 =0
R( R-4) -1( R-4) = 0
(R-1) (R-4) = 0
R = 1,4
so R can be either 1 or 4
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