Question 253: Current Electricity

Question

A galvanometer of resistance G is converted
into a voltmeter of range 0 – 1 V by connecting
a resistance R1 in series with it. The additional
resistance that should be connected in series
with R1 to increase the range of the voltmeter
to 0 – 2 V will be :

Accepted Answer

1 = i
g
(G + R
1
) ....(1)
2 = i
g
(R
1
+ R
2
+ G)  ....(2)
Doing (1) $$ \div $$ (2), we get
$${1 \over 2} = {{{i_g}\left( {G + {R_1}} \right)} \over {{i_g}\left( {G + {R_1} + {R_2}} \right)}}$$
$$ \Rightarrow $$ R
1
+ R
2
+ G = 2R
1
+ 2G
$$ \Rightarrow $$ R
2
= R
1
+ G

Answer

G

Answer

R1

Answer

R1 + G

Answer

R1 - G

Current Electricity

A galvanometer of resistance G is converted into a voltmeter of range 0 – 1 V by connecting a resistance R1 in series with it. The additional resistance that should be connected in series with R1 to increase the range of the voltmeter to 0 – 2 V will be :

Choose the correct answer: