How can I calculate the compression of a support column under a heavier weight?

AI Thread Summary
To calculate the compression of a support column under a heavier weight, the equation F=KX is used, where F is the force, K is the stiffness, and X is the compression. Given a weight of 5.42 x 10^5 N causing a compression of 2.46 x 10^-4 m, the stiffness K is calculated to be approximately 2.2 billion N/m. Using this K value, the compression under a new weight of 4.8 x 10^6 N is found to be 0.0022 m, confirming the calculations are correct. An alternative method using a ratio also yields the same result, demonstrating the consistency of the solution. The discussion emphasizes the importance of understanding elastic behavior in accordance with Hooke's law.
kkmonte
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Homework Statement



A support column is compressed 2.46 x 10^ -4m under a weight of 5.42 X 10^5N. how much is the column compressed under a weight of 4.8 X10^6N?

Homework Equations



F=KX

The Attempt at a Solution



By using that equation, I get 542000 = .000246K



Solve for K, and I get a huge number, 2,203,252,032.52



Then by using that number as my new K, and solving for the compressed distance with the new weight, I get 0.0022 m.



Is that the right answer?



Similarly, I figured I could just make a ratio proportion of:



.000246....X

------------- = ----------------

542,000....4,800,000



Which also gives me an answer of 0.0022 m (2.2 X 10^ -3). Is this correct?
 
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Yes, either method gives you the correct solution, as long as the column is still behaving elastically in accordance with Hooke's law.
 
Thanks Jay, when I first did this problem, I was looking at the answer of 2.2e-3 and shaking my head going how can this thing compress less when there is a heavier weight on it? However it wasn't after I was typing it in the computer that I realized that the first compression is 2.46e-4, and I went, duh. =)

Thanks for letting me know I'm correct.
Ken
 
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