What Happens to Wire Resistance When Stretched?

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When a wire is stretched to seven times its original length while maintaining its volume, its resistance increases significantly. The original resistance of 0.008 ohms will become 49 times greater due to the increase in length and decrease in cross-sectional area. This means the new resistance will be 0.392 ohms. The confusion arises from the relationship between resistance, length, and area, which is governed by the formula R = ρL/A. Understanding this relationship clarifies how stretching affects resistance.
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Simple Resistance Problem...help!

Homework Statement


A wire has a resistance of 0.008 W. What will the wire's resistance be if it is stretched to seven times its original length without changing the volume of the wire? (Give answer in W.)


Homework Equations



R = Ch in V / I

The Attempt at a Solution


I thought I would just multiply 0.008 by 7? But that's not right...I know this must be so easy but for some reason I am stuck!
 
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does anyone know how to do this?
 
how resistance can be measured in watts instead omms? Maybe power which going through wire is 0.008 W and if wire will be 7 times longer then power will be 7 times smaller or resistance will be 7 times bigger. But possible that resistance will be 7*7=49 times bigger becouse, if you would have 7 times longer wire it would have 7 times bigger resistance, but becouse wire is also 7 thiner, then at all resistance will be 49 times bigger.
 

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