Question

In a metre bridge experiment, unknown resistance X and known resistance of `60Omega` is connected in left and right gap of a metre bridge respectively. If the null point is obtained at 40 cm from the left end then the unknown resistance is
A. `20Omega`
B. `40Omega`
C. `60Omega`
D. `80Omega`

Answer 1

Correct Answer - B
`X=(l_(x))/(l_(r))R=(40xx60)/(60)=40Omega`