The length of potentiometer wire is $4 \mathrm{~m}$ and is connected in series with an accumulator. The e.m…
The length of potentiometer wire is $4 \mathrm{~m}$ and is connected in series with an
accumulator. The e.m.f. (Unknown) of a cell balances against $1 \cdot 5 \mathrm{~m}$ length of wire.
If the length of potentiometer wire is doubled, then the new balancing length of
wire will be
$4.5 \mathrm{~m}$
$1.5 \mathrm{~m}$
$0.75 \mathrm{~m}$
$3 \mathrm{~m}$
Solution
If the length is doubled, potential gradient will be half. So to balance the same battery it will take double the length.
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