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A uniform conducting slab is cut lengthwise into two equal halves, each having half the original cross-sectional area but the same length. The resistance of each half is
Ahalf the original
Bequal to the original
Ctwice the original
Dfour times the original
Answer & Solution
Correct answer: C. twice the original
1. Resistance is inversely proportional to area: $R \propto 1/A$.
2. Halving the cross-sectional area (length fixed) doubles the resistance.
3. So each half-slab has resistance $2R$.
4. Half and equal ignore the area dependence; four times double-counts the effect.
_Source: NCERT Class 12 Physics Ch 3 "Current Electricity", p.3_
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