Andrew Mason's latest activity
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Andrew Mason replied to the thread Does David Reich contradict Nicholas Wade?.This graphic from the paper published in Nature in 2015 may help explain the data that Reich was using: The green bars represent the... -
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Andrew Mason replied to the thread Undergrad Measured Spectrum of Stopped Wood Organ Pipe Shows ALL Overtones.So 3 times the fundamental is a harmonic (a twelfth) but not 1.5 (fifth). You might find musicians who would disagree that a perfect...
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Andrew Mason replied to the thread Undergrad Measured Spectrum of Stopped Wood Organ Pipe Shows ALL Overtones.The OP was using "overtones" to refer to the sequential harmonics above the fundamental tone. I was just doing the same. I don't think...
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Andrew Mason replied to the thread Does David Reich contradict Nicholas Wade?.It depends on whether these statements can be true: 1. "most Europeans are descended from the first settlers who arrived during the...
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Andrew Mason replied to the thread Viral (RNA and DNA) polymerases, inhibitors and antiviral drugs.As someone with a long held interest in, but no academic background in, molecular biology, I find this is helpful. I became interested...
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Andrew Mason replied to the thread Does David Reich contradict Nicholas Wade?.There is a difference, not necessarily a total contradiction. Based on genetic analysis of European skeletons older than 5000 years...
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Andrew Mason reacted to haruspex's post in the thread Finding proper value for centripetal acceleration in a plane rising up with
Like.
Yes, I do realise that. The purpose of my post was to challenge the statement I quoted in post #12 in a way that might convince the... -
Andrew Mason replied to the thread Finding proper value for centripetal acceleration in a plane rising up.Yes. But it is not flying level at the bottom portion of the flight path, which is a quarter circle with radius 300m. AM
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Andrew Mason replied to the thread Finding proper value for centripetal acceleration in a plane rising up.The question is a bit of a trick question. It says the maximum upward acceleration is 6g. The correct answer is given by...
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Andrew Mason replied to the thread Undergrad Measured Spectrum of Stopped Wood Organ Pipe Shows ALL Overtones.Interesting point. The only opening for sound is the mouth of the pipe and for sound energy to exit there is an acoustic coupling...
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Andrew Mason replied to the thread Undergrad Measured Spectrum of Stopped Wood Organ Pipe Shows ALL Overtones.Yes, but the stopped wooden organ pipe does not produce a square wave. I am not suggesting that the physics of musical instruments is...
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Andrew Mason reacted to Astronuc's post in the thread Undergrad Abundant water from primordial supernovae at cosmic dawn with Like.
https://www.nature.com/articles/s41550-025-02479-w, published 3 March 2025 It's those Population III stars again...
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Andrew Mason replied to the thread Undergrad Measured Spectrum of Stopped Wood Organ Pipe Shows ALL Overtones.Right. That is how the vibrations originate. So I am confused by your previous reference to "Even harmonics are generated by...
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Andrew Mason replied to the thread Undergrad Measured Spectrum of Stopped Wood Organ Pipe Shows ALL Overtones.?? In an organ pipe, the harmonics do not result from clipping sound wave amplitudes. The fundamental and harmonics are generated by...
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Andrew Mason replied to the thread Undergrad Measured Spectrum of Stopped Wood Organ Pipe Shows ALL Overtones.The terms are interchangeable - at least for our purposes. This is a fairly short pipe so there may be some end effects, lip anomalies...
