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Question
The figure given below shows three resistors?
Their combined resistance is:
(a) `1 5/7`Ω
(b) `14` Ω
(c) `6 2/3` Ω
(d) `7 1/2` Ω
Solution
(d) `7 1/2`Ω
The resistors of 6and 2 are connected in parallel
∴ `1/R=1/R_1+1/R_2`
Here,
`R_1=6`Ω
`R_2=2` Ω
`1/R=1/6+1/2`
`1/R=4/6`
`R=6/4`
This arrangement is further connected in series with the 6 resistor
∴Net resistance` =6/4+6=7 1/2` Ω
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