How Far Does a Spring Stretch with a 5 kg Weight?

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SUMMARY

The discussion centers on calculating the stretch of a spring when a 5 kg weight is applied, using Hooke's Law with a spring constant of 0.038 N/m. The net force acting on the spring is zero since the weight is in equilibrium, leading to the equation 0.038X + 5(-9.8) = 0. The solution reveals that the spring stretches 1289.47 meters, indicating a miscalculation in the final answer, as this value is unreasonably high for practical applications. The correct approach emphasizes understanding the balance of forces rather than acceleration.

PREREQUISITES
  • Understanding of Hooke's Law (Fsp = -kX)
  • Basic knowledge of forces (Fnet = ma)
  • Familiarity with gravitational force calculations (Fg = mg)
  • Concept of equilibrium in physics
NEXT STEPS
  • Review the principles of Hooke's Law and its applications in real-world scenarios.
  • Learn about equilibrium conditions in static systems.
  • Explore the implications of spring constants in different materials.
  • Investigate the effects of mass and gravity on spring displacement.
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and spring dynamics, as well as educators seeking to clarify concepts of force and equilibrium.

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Homework Statement



A 5 kg weight hangs on a spring with spring constant k = 0.038 n/m. How far does the spring stretch?


Homework Equations



Fsp = -kX

Fnet = Fsp + Fg


The Attempt at a Solution



So I already know that Fsp = 0.038X and that Fnet = ma = 5 (-9.8)

So -49 = 0.038X + Fg.

But isn't the force of gravity equal to 5(-9.8) as well? Am I approaching the problem incorrectly?
 
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So the spring is hanging. Its not accelerating. Its just dangling there. So sum of forces is zero. Try that.
 
So if Fnet = 0

| Fsp
o
| Fg

Fsp + Fg = Fnet = 0

kX + mg = 0

0.038X + 5 (-9.8) = 0

0.038X = 49

X = 1289.47 Meters?

Thanks I didn't think about it not accelerating.
 
Looks good. Didn't check numbers. Glad I could help. Good luck on your future physics endeavors.
 

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