A current passes through a wire of nonuniform | vedclass

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(D) When a steady current $I$ flows through a wire of non-uniform cross-section,the current $I$ remains constant at every cross-section of the wire.$1

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Both $(A)$ and $(C)$.

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(D) When a steady current $I$ flows through a wire of non-uniform cross-section,the current $I$ remains constant at every cross-section of the wire.$1$. The charge $q$ crossing a given cross-section in a time interval $t$ is given by $q = I 	imes t$. Since $I$ is constant,the charge crossing is independent of the cross-section.$2$. The free-electron density $n$ is a property of the material of the wire and is independent of the geometry or cross-section of the wire.$3$. The drift velocity $v_d$ is related to current by $I = n e A v_d$. Since $I$ and $n$ are constant,$v_d$ must change if the cross-sectional area $A$ changes.Therefore,both the charge crossing in a given time interval and the free-electron density are independent of the cross-section.

$A$ current passes through a wire of nonuniform cross-section. Which of the following quantities are independent of the cross-section?

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