# Question

As a wire is stretched out so that its length increases, its cross-sectional area decreases, while the total volume of the wire remains constant.

(a) Will the resistance after the stretch be (1) greater than, (2) the same as, or (3) less than that before the stretch?

(b) A 1.0-m length of copper wire with a 2.0-mm diameter is stretched out; its length increases by 25% while its cross-sectional area decreases, but remains uniform. Compute the resistance ratio (final to initial).

(a) Will the resistance after the stretch be (1) greater than, (2) the same as, or (3) less than that before the stretch?

(b) A 1.0-m length of copper wire with a 2.0-mm diameter is stretched out; its length increases by 25% while its cross-sectional area decreases, but remains uniform. Compute the resistance ratio (final to initial).

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