Ametallic conductor of irregular cross-section is as shown in the figure. Aconstant potential difference is applied across the ends $(1)$ and $(2)$. Then :
Diffcult
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$(A) I_{P}=I_{Q}$
$(B) J=\sigma E$
$J_{P} < J_{Q}$
$E p < E_{Q}$
$(C)$ $H=I^{2} R \& R \propto \frac{1}{A}$
$R_{P} < R_{Q}$
$H_{P} < H_{Q}$
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