A wire is connected to a battery between the point $M$ and $N$ as shown in the figure $(1)$. The same wire is bent in the form of a square and then connected to the battery between the points $M$ and $N$ as shown in the figure $(2)$. Which of the following quantities increases?
A
Heat produced in the wire and resistance offered by the wire.
B
Resistance offered by the wire and current through the wire.
C
Heat produced in the wire, resistance offered by the wire and current through the wire.
D
Heat produced in the wire and current through the wire.
Medium
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A
Heat produced in the wire and resistance offered by the wire.
a (a)
When the wire is bent in the form of a square and connected between $M$ and $N$ as shown in fig.$(2)$, the effective resistance between $M$ and $N$ decreases to one fourth of the value in fig.$(1)$. The current increases four times the initial value according to the relation $V=I R$. Since $H=I^2 R t$, the decrease in the value of resistance is more than compensated by the increases in the value of current. Hence heat produced increases. Percentage loss in energy during the collision $\simeq 56 \%$
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