Question

Solve above question correctly​

Answer 1

S O L U T I O N

The relation between length and area is

R = ρl/A _[i]

Where ρ being specific resistance is the proportionality constant and depends on the nature of material.

[i] Length = L/2, area = 2A

Putting in Eq [i] we have

R = ρ( L/2 )/2A = ρL/4A

[ii] Length = L, area = A

Putting in Eq [i] we have

R = ρL/A

[iii] Length = 2L area = A/2

Putting in Eq [i] we have

R = ρ 2L/ A/2 = 4ρL/A

As it is understood from above, resistance is minimum only in option b!

Answer 2

Answer:

So, Resistance is minimum in Wire of Cross-sectional area 2A.

Explanation:

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