Question

A wire of resistance 20 ohm is melted to form a new wire of half of its cross-section arear, find out the resistance of new wire?​

Answer 1

Answer:

Since, when the length is doubled, cross sectional area of the wire becomes half. R = 80 ohm.

Explanation:

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Answer 2

Answer:

Given resistance = R1 = 20 ohm

Given resistance = R1 = 20 ohmLet length of the wire = L

Given resistance = R1 = 20 ohmLet length of the wire = LTherefore, new length of the wire = 2L

Given resistance = R1 = 20 ohmLet length of the wire = LTherefore, new length of the wire = 2LSince, when the length is doubled, cross sectional area of the wire becomes half.

Given resistance = R1 = 20 ohmLet length of the wire = LTherefore, new length of the wire = 2LSince, when the length is doubled, cross sectional area of the wire becomes half.Therefore, new resistance = R = 2L/ (A/2) =4L/A

Given resistance = R1 = 20 ohmLet length of the wire = LTherefore, new length of the wire = 2LSince, when the length is doubled, cross sectional area of the wire becomes half.Therefore, new resistance = R = 2L/ (A/2) =4L/AR = 4 x 20 (since, L/A = resistance)

Given resistance = R1 = 20 ohmLet length of the wire = LTherefore, new length of the wire = 2LSince, when the length is doubled, cross sectional area of the wire becomes half.Therefore, new resistance = R = 2L/ (A/2) =4L/AR = 4 x 20 (since, L/A = resistance)R = 80 ohm.

Explanation:

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