R 1 , R 2 , R 3 are different values of R . A , B and C are the null points obtained corresponding to R 1 , R 2 and R 3 respectively. For which resistor, the value of X will be the most ac

Question

R 1 ​ , R 2 ​ , R 3 ​ are different values of R . A , B and C are the null points obtained corresponding to R 1 ​ , R 2 ​ and R 3 ​ respectively. For which resistor, the value of X will be the most accurate and why? (JEE 2005)

TestHub · Accepted Answer

A slide-wire bridge is most sensitive when the null point lies near the middle of the wire; there the percentage error in the measured balance length is least.

Of the three null points, $B$ (obtained with $R_{2}$ ) is closest to the middle, so $R_{2}$ gives the most accurate value of $X$ .

Physics - Current Electricity Question with Solution | TestHub

Options:

Doubts & Discussion