Question on free vibration
2010-01-15 8:14 am
Mass of weight 90N is attached to the end of a spring, If the mass is released very slowly, the spring extended with a distance of 100mm. What is the natural frequency of the system in Hz?
回答 (1)
2010-01-15 8:46 am
✔ 最佳答案
Assuming the spring is light.When the weight is released very slowly, at the extension, the restoring force in the spring balances the weight of the mass.
So, by Hooke's law
F = kx
mg = kx
90 = k(100 X 10^-3)
Spring constant, k = 900 Nm^-1
The period of the system in free vibration, T
= 2pi sqrt(m/k)
= 2pi sqrt(90/(9.8)(900))
= 0.635 s
So, the natural frequency, f
= 1/T
= 1/0.635
= 1.58 Hz
參考: Physics king
收錄日期: 2021-04-19 21:11:09
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20100115000051KK00024