Question

A wheatstone bridge is used to determine the value of unknown resistance $X$ by adjusting the variable resistance $Y$ as shown in the figure. For the most precise measurement of $X$, the resistances $P$ and $Q$ :

• A. do not play any significant role
• B. should be approximately equal to $2 X$
• C. should be approximately equal and are small
• D. should be very large and unequal

Answer 1

Answer: (C)

Resistance of $P \& Q$ should be approx. equal as it decreases error in experiment.