Question

A given length of wire is doubled.By what factors does the restance of wire change.

Answer 1

we know -

resistance of the wire is directly proportional to the length of the wire.

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when the length is doubled the resistance increases by square of the original resistance.

Answer 2

When the length of a wire is doubled, its resistance gets doubled. So ,When this process is repeated again, the resistance of the wire becomes four times of the original resistance.