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Question
A wire has a length of 2.0 m and a resistance of 5.0 Ω. Find the electric field existing inside the wire if it carries a current of 10 A.
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Solution
Given:-
Length of the wire, l = 2 m
Resistance of the wire, R = 5 Ω
Current through the wire, i = 10 A
From Ohm's Law, the potential difference across the wire,
V = iR
∴ V= 10 × 5 = 50 V
Electric field,
\[E = \frac{V}{l}\]
\[ = \frac{50}{2}\]
\[ = 25 V/m\]
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