Question: Q. 1. A resistance is to be measured using a meter bridge. Student chooses the standard resistance to be . He finds the null point at . He is told to attempt to improve the accuracy. Which of the following is a useful way?
(a) He should measure more accurately.
(b) He should change to and repeat the experiment.
(c) He should change to and repeat the experiment.
(d) He should give up hope of a more accurate measurement with a meter bridge.
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Solution:
Ans. Correct option : (c)
Explanation : To calculate resistance,
So to get balance point near to (middle) we have to take , as here implies that is nearly 33 times to .
In order to make ratio and , we must take the resistance .