Damping constant and angular frequency

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The discussion centers on the relationship between the damping constant (b) and the angular frequency (ω') of a damped harmonic oscillator. The formula for ω' indicates that if b is small compared to the square root of km, then ω' approximates the undamped frequency (ω). The user questions whether the condition b << √(2km) represents a significant difference compared to b << √(km). Responses clarify that both conditions are effectively equivalent in practical terms when discussing quantities that are much smaller than others. Overall, the nuances in these expressions do not alter the fundamental understanding of damped harmonic motion.
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While discussing ω^{&#039;}, the angular frequency of a damped harmonic oscillator, given by:
ω^{&#039;}=\sqrt{\frac{k}{m}-\frac{b^{2}}{4m^{2}}}
where k is the "springiness", m is the mass, and b is the damping constant,
my book, Halliday, Resnick and Walker, says if b is small but not zero,b&lt;&lt;\sqrt{km} then ω^{&#039;}\approxω. ω=\frac{k}{m}, the undamped frequency.

If I say that \frac{k}{m}&gt;&gt;\frac{b^{2}}{4m^{2}}and go through the algebra to get the relation in the book, I get b&lt;&lt;\sqrt{2km}
Is this a meaningful difference when talking about a quantity that is much, much less than another?
Thanks for any help.
 
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The two statements, b \ll \sqrt{km} \text{ and } b \ll \sqrt{2km}, are essentially considered to be equivalent statements.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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