Vibrations and differential equations.

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SUMMARY

The discussion centers on formulating a differential equation for the motion of an undamped spring with a natural frequency of 1/2 and a weight of 32 lb. The equation is derived from the standard form my'' + ky = F_ocosωt, leading to the conclusion that k equals 8. The participants clarify that the problem assumes no external force, indicating F_o = 0, and seek to relate the given natural frequency to the angular frequency ω. The key takeaway is the relationship between natural frequency and angular frequency, which is ω = 2πf.

PREREQUISITES
  • Understanding of differential equations, specifically second-order linear equations.
  • Knowledge of spring dynamics and natural frequency concepts.
  • Familiarity with the relationship between natural frequency and angular frequency.
  • Basic principles of undamped harmonic motion.
NEXT STEPS
  • Study the derivation of the differential equation for undamped harmonic oscillators.
  • Learn about the relationship between natural frequency and angular frequency in detail.
  • Explore examples of undamped spring-mass systems to reinforce understanding.
  • Investigate the impact of external forces on differential equations of motion.
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Students studying differential equations, physics enthusiasts, and engineers focusing on mechanical vibrations and harmonic motion.

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Homework Statement



Suppose the motion of a spring has natural frequency 1/2 and is undamped. If the weight attached is 32lb, write a differential equation describing the motion.

Homework Equations



my''+ky=F_ocosωt

32y"+8y=?

ω_o= (k/m)^.5

The Attempt at a Solution



→ .5=(k/32)^.5 → k=8

gamma=0

32y"+8y=?My problem is that I don't know how to find F_o or ω. Is this question referring to that of a no external force case? Or am I missing some equation that will help me find this?
 
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The question is implying that there is no external forcing to F0 = 0. As for ω, they gave you the natural frequency f. How does this relate to the angular frequency ω?
 

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