Will the spring stretch or compress?

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yesmale4
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Homework Statement
A spring (k = 711 N/m) is attached to the ceiling of an elevator. How much will the spring stretch (relative to its unstretched length), if a 5.8 kg object is attached to the lower end and the elevator is accelerating downward at 0.41 m/s2?
Relevant Equations
Hooke's law
F=ma
Online homework screenshot: spring problem text with an entered answer of -0.0833 m, marked Incorrect, with a hint reading Solve for net force on spring, then use k to find displacement.

Handwritten working on squared paper: given k = 711 N/m, m = 5.8 kg, a = 0.41 m/s², g = 9.81 m/s²; Hooke's law F = -kx, then Newton's second law F - mg = ma leads to x = -m(a+g)/k, giving x = -0.0833 m.


i would like to understand why my answer is incorrect i don't know what I am doing wrong i would like for some help
 
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  • Handwritten working on graph paper: given k = 711 N/m, m = 5.8 kg, a = 0.41 m/s^2, g = 9.81 m/s^2; Hooke's law F = -kx rearranged to x = -F/k, Newton's second law F - mg = ma giving F = m(a + g), then x = -m(a + g)/k = -5.8(0.41 + 9.81)/711, result x = -0.0833 m.
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Is the effective acceleration of gravity when the elevator is accelerating down greater or less than g = 9.81 m/s2?
 
kuruman said:
Is the effective acceleration of gravity when the elevator is accelerating down greater or less than g = 9.81 m/s2?
less
 
anuttarasammyak said:
Acceleration of elevator downward lessen g which amounts 9.8-0.4 downward.
i try this i did (-5.8*(9.81-0.41))/711 and get -0.0766m and its still the wrong answer