JEE PYQ: Experimental Physics Question 11
Question 11 - 2020 (05 Sep 2020 Shift 1)
A galvanometer of resistance G is converted into a voltmeter of range $0 - 1$ V by connecting a resistance $R_1$ in series with it. The additional resistance that should be connected in series with $R_1$ to increase the range of the voltmeter to $0 - 2$ V will be:
(1) $G$
(2) $R_1$
(3) $R_1 - G$
(4) $R_1 + G$
Show Answer
Answer: (4)
Solution
$V = i_g(G + R_1)$ … (i). For 0-2 V: $2 = i_g(R_1 + R_2 + G)$ … (ii). Dividing: $\frac{1}{2} = \frac{G + R_1}{G + R_1 + R_2}$. So $R_2 = G + R_1$.
BETA
