# Physics!! Help!!!!!

A wire of length L and cross-sectional area A has resistance R. What will be the resistance R_stretched of the wire if it is stretched to twice its original length? Assume that the density and resistivity of the material do not change when the wire is stretched.

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1. The product L*A remains constant after stretching. If L doubles, A decreases by 1/2

Resistance is proportional to L/A.

R2/R1 = L2/L1 *A1/A2 = 4

R1 is the original resistance and R2 is the final resistance.

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2. A)becomes double B)remains same C)becomes half C)becomes square

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3. Remain same

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4. Consider a c-Si solar cell whose fingers have a resistance R=0.1 Ohm. What would be the finger's resistance (in Ohm) if the finger's width is doubled and the finger's height is one third of its initial value?

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