A constant current of 0.1 A is passed through a copper wire by applying potential difference of 3 V across the wire. The resistance of the wire is:
The correct answer is (D) 30 Ω
Given:
V is the potential difference = 3 V
I is the current = 0.1 A
R is the resistance = ?
Formula used:
By Ohms law V = I . R
Rearrange the formula: R =
R = = 30 Ω
Hence, the resistance is 30 Ω.
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