JEE PYQ: Experimental Physics Question 7
Question 7 - 2020 (02 Sep 2020 Shift 2)
A potentiometer wire $PQ$ of 1 m length is connected to a standard cell $E_1$. Another cell $E_2$ of emf 1.02 V is connected with a resistance ‘r’ and switch $S$ (as shown in figure). With switch $S$ open, the null position is obtained at a distance of 49 cm from $Q$. The potential gradient in the potentiometer wire is:
(1) 0.02 V/cm
(2) 0.01 V/cm
(3) 0.03 V/cm
(4) 0.04 V/cm
Show Answer
Answer: (1)
Solution
Potential gradient $x = \frac{\text{Potential drop}}{\text{length}}$. Balancing length from $P = 100 - 49 = 51$ cm. $x = \frac{1.02}{51} \approx 0.02$ V/cm.
BETA
