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प्रश्न
Define Current density.
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उत्तर
Current density is a vector quantity, often known as an area vector or cross-sectional area vector, whose value is equal to the electric current flowing per unit area.
J = `"I"/"A"`
S.I unit is A/m2.
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संबंधित प्रश्न
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What length of copper wire of resistivity 1.7 × 10-8 Ω m and radius 1 mm is required so that its resistance is 2Ω?
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(i) Metal and
(ii) Semiconductor ?
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Choose the correct alternative.
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