Resistances of three resistors are in the proportion connected in parallel, their effective resistance is `6 Omega`. Then connect on if these resistance are connect in series so equivalent resistance will be .......

Options

A. `36 Omega`
B. `84 Omega`
C. `66 Omega`
D. `18 Omega`

Answer

C

Explanation

`66 Omega`
Suppose resistance is R.
`therefore` We get three resistance R : 2R : 3R. equivalent resistance on connecting these three resistance in parallel,
`(1)/(6) = (1)/(R) + (1)/(2R) + (1)/(3R) = (6 + 3 + 2)/(6R) = (11)/(6R)`
`therefore (6R)/(6) = 11 `
`therefore R = 11 Omega`
Now each resistance `11 Omega, 22 Omega , 33 Omega`
`therefore ` Equivalent resistance in series connection
`R_(S) = 11 + 22 + 33 therefore R_(S) = 66 Omega`