Physics · 2021
JEE Main · 4 August 2021, Shift 1 · Q21
A wire of length L is coated by another conducting material of double resistivity and the thickness of the layer is equal to the radius of the wire.…
A wire of length L is coated by another conducting material of double resistivity and the thickness of the layer is equal to the radius of the wire. The resistance of the wire between its ends after coating will decrease by \_\_\_\_%.
Official answer
60
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.