Elastic Restoring Force- Spring Constant

AI Thread Summary
A bug with a mass of 0.20g causes a spider's web to vibrate at a frequency of 18 Hz, prompting a calculation of the spring constant. The relevant equations include the relationship between frequency, mass, and spring constant. The user initially struggled with the calculation but later clarified the correct approach to find the spring constant using the formula k = 4π²*m*T², ensuring mass is in kilograms. The final calculated spring constant is approximately 2.6 N/m. Understanding the units of the spring constant is crucial for solving similar problems.
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Homework Statement


A bug having a mass of 0.20g falls into a spider's web, setting it into vibration with a dominant frequency of 18 Hz. Find the corresponding spring constant.


Homework Equations


1. f=\frac{1}{T}

2. \omega=2\pif

3. [natural angular frequency], \omega0=\sqrt{\frac{k}{m}}

4. [natural linear frequency], f0=\frac{1}{2\pi}*\sqrt{\frac{k}{m}}


The Attempt at a Solution



My thought was to plug the mass in for m and the frequency in for f0 and then solve for k in equation 4, but I am getting an answer very different from the given answer, which is 2.6 N/m. My main question is on the units of the spring constant, I think I am missing just where this unit arises from, and I think I should be able to solve the problem if I can understand that, but I must be missing something. I would very much appreciate any thoughts on this.
 
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Addendum: continued working and solved problem, but here is answer in case anybody else on this forum has a similar problem/issue.

To calculate spring constant from frequency and mass:

Start with equation T=2\pi\sqrt{\frac{m}{k}}

Use algebra to solve for k, k=4\pi<sup>2</sup>*m*T2

Know that T is frequency, so plug in Hz for T and be sure to convert mass to kilograms..

Giving final answer of 2.5582~2.6N/m
 
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