Question

In Wheatstone's network p = 2 `Omega` , Q = 2 `Omega`, R = 2 `Omega` and S = 3 `Omega`. The resistance with which S is to be shunted in order that the bridge may be balanced is ______.

Options

• 40 `Omega`

• 1 `Omega`

• 6 `Omega`

• 2 `Omega`

Answer 1

In Wheatstone's network p = 2 `Omega` , Q = 2 `Omega`, R = 2 `Omega` and S = 3 `Omega`. The resistance with which S is to be shunted in order that the bridge may be balanced is 6 `Omega`. 

Explanation:

`"P"/"Q" = "R"/"S'"` (For balancing of bridge)

`2/2 = 2/"s'"`

`1/"s'" = 1/3 + 1/"r"`

∴ `1/2 = 1/3 + 1/"r"`

∴ `1/"r" =1/2 - 1/3 = 1/6`

∴ 6 `Omega`