Stress and Strain, simple question Just need a clarification

AI Thread Summary
The discussion centers on calculating the stretch of a steel cable under tension. The user is trying to determine the area (A) for the formula relating stress and strain, specifically using the equation F/A = Y (delta L / L0). They clarify that the area for a circular cable can be found using A = πr², converting the radius to meters. The user expresses confidence in their approach after realizing the correct formula for area. The conversation concludes with a focus on applying the correct parameters to solve for the cable's stretch.
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Homework Statement



A tow truck is pulling a car out of a ditch by means of a steel cable that is 9.1 m long?
and has a radius of 0.50 cm .when the car just begins to ,move , the tension in the cable is 980 N. how much has the cable stretched?

Y steel= 2.0 x 10¹¹ N m²

Homework Equations



F/A = Y (delta L / L0 )


The Attempt at a Solution



We just need to solve for delta L, but I am having difficulty figuring out what A would be - any help? What A formula for the cable do I use?
 
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nvermind I think I got it!

890/(2pi*r(in meters) = Y (delta L/9.1)

is this correct?
 
the A in the equation is area, the steel is circular to A=\pi r^2 and convert r to metres.
 
thanks so much!
 
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