Question

A wire has a diameter d and resistance R. If the diameter is made 3d, the length and material remaining the same, the new value of resistance will be

a.

R/3

b.

3 R

c.

R/9

d.

9 R

Answer: (c).R/9

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Q. A wire has a diameter d and resistance R. If the diameter is made 3d, the length and material remaining the same, the new value of resistance will be

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