A) 0
because all of the forces cancel out, so it is not moving with balanced forces.
Answer:
The motion is over-damped when λ^2 - w^2 > 0 or when
> 0.86
The motion is critically when λ^2 - w^2 = 0 or when
= 0.86
The motion is under-damped when λ^2 - w^2 < 0 or when
< 0.86
Explanation:
Using the newton second law
k is the spring constante
b positive damping constant
m mass attached
x(t) is the displacement from the equilibrium position
![\frac{d^{2} x}{dt^{2}} +\frac{b}{m}\frac{dx}{dt} + \frac{k}{m}x = 0](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5E%7B2%7D%20x%7D%7Bdt%5E%7B2%7D%7D%20%2B%5Cfrac%7Bb%7D%7Bm%7D%5Cfrac%7Bdx%7D%7Bdt%7D%20%2B%20%5Cfrac%7Bk%7D%7Bm%7Dx%20%3D%200)
Converting units of weights in units of mass (equation of motion)
![m = \frac{W}{g} = \frac{14}{32} = 0.43 slug](https://tex.z-dn.net/?f=m%20%3D%20%5Cfrac%7BW%7D%7Bg%7D%20%3D%20%5Cfrac%7B14%7D%7B32%7D%20%3D%200.43%20slug)
From hook's law we can calculate the spring constant k
![k = \frac{W}{s} = \frac{14}{2} = 7 lb/ft](https://tex.z-dn.net/?f=k%20%3D%20%5Cfrac%7BW%7D%7Bs%7D%20%3D%20%5Cfrac%7B14%7D%7B2%7D%20%3D%207%20lb%2Fft)
If we put m and k into the DE, we get
![\frac{d^{2} x}{dt^{2}} +\frac{b}{0.43}\frac{dx}{dt} + 16.28x = 0](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5E%7B2%7D%20x%7D%7Bdt%5E%7B2%7D%7D%20%2B%5Cfrac%7Bb%7D%7B0.43%7D%5Cfrac%7Bdx%7D%7Bdt%7D%20%2B%2016.28x%20%3D%200)
Denoting the constants
2λ =
= ![\frac{b}{0.43}](https://tex.z-dn.net/?f=%5Cfrac%7Bb%7D%7B0.43%7D)
λ = b/0.215
![w^{2} = \frac{k}{m} = 16.28](https://tex.z-dn.net/?f=w%5E%7B2%7D%20%3D%20%5Cfrac%7Bk%7D%7Bm%7D%20%3D%2016.28)
λ^2 - w^2 = ![\frac{b^{2} }{0.046} - 16.28](https://tex.z-dn.net/?f=%5Cfrac%7Bb%5E%7B2%7D%20%7D%7B0.046%7D%20-%2016.28)
This way,
The motion is over-damped when λ^2 - w^2 > 0 or when
> 0.86
The motion is critically when λ^2 - w^2 = 0 or when
= 0.86
The motion is under-damped when λ^2 - w^2 < 0 or when
< 0.86
My guess would be about 10 years because stars are hot balls of light that are reflections from years ago so it would most likely take awhile
Mass is measured in kg
Velocity is measured in ms^-1
Hope this is what you were looking for