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How Raganwald Lost His Crown

braythwayt.com

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Re: How Raganwald Lost His Crown

#21

Post by TeMPOraL »

bryanl wrote: post #15
WaxProlix wrote: post #14

Earlier quoted context omitted.

> I would have found that while my scale tells me that I am about 86 kilograms on Earth, I would have weighed 8.6 trillion kilograms on this neutron star. Kilograms are a measure of mass, not weight. Pounds would be a more appropriate unit there.

Most of the people world weigh themselves in kilograms.

Because they're interested in knowing their mass, not their weight. Weighing is done using scales, which have a hardcoded division by gravitational acceleration of Earth on its... scales.

Re: How Raganwald Lost His Crown

#22

Post by bloat »

braythwayt wrote: post #17
bryanl wrote: post #15

Earlier quoted context omitted.

Most of the people world weigh themselves in kilograms.

True, but WaxProlix is correct. Ten kilograms is 22 pounds on Earth, but 2.2 trillion pounds on the given Neutron Star.

I was going to jump in and say that the pound is also a unit of mass. But it turns out its both.

https://en.wikipedia.org/wiki/Pound_(force) https://en.wikipedia.org/wiki/Pound_(mass)

Re: How Raganwald Lost His Crown

#23

Post by braythwayt »

bloat wrote: post #22
braythwayt wrote: post #17

Earlier quoted context omitted.

True, but WaxProlix is correct. Ten kilograms is 22 pounds on Earth, but 2.2 trillion pounds on the given Neutron Star.

I was going to jump in and say that the pound is also a unit of mass. But it turns out its both. https://en.wikipedia.org/wiki/Pound_(force) https://en.wikipedia.org/wiki/Pound_(mass)

And then there's the foot-pound, a unit of torque much prized by the owners of muscle cars until eclectric vehicles went from obscure to early-adopter status.

Re: How Raganwald Lost His Crown

#24

Post by saagarjha »

> I might have lifted my Apple Watch and said “Hey Siri, record a note.” If I was using the Apple Neutron Star Edition Apple WatchOS, it would have had to correct for time dilation between time at my waist and time at my shoulder.

Would it, really? Using a back-of-the-envelope calculation using a formula pulled from Wikipedia[1], and assuming:

1. The Apple Watch needs to stay within 50 milliseconds as Apple advertises

2. The neutron star is around two solar masses and has a radius of 10 km, and isn't spinning faster than 1,000 times a second

3. The distance between your waist and shoulder is about a meter

it should take a couple hundred seconds before Apple Watch drifts out of sync. Should be long enough for Siri to record your note :)

[1]https://en.wikipedia.org/wiki/Gravitational_time_dilation#Ou...

Re: How Raganwald Lost His Crown

#25

Post by thaumasiotes »

WaxProlix wrote: post #18
bryanl wrote: post #15

Earlier quoted context omitted.

Most of the people world weigh themselves in kilograms.

They roughly infer their mass (in kilograms) by assuming 9.8m/s/s gravitational acceleration and using a scale to judge how much mass the resulting 'push' would require given that pull. A scale would tell you that you weight slightly less at the top of a mountain than at sea level, though in reality you'd have the same mass. Same is true on a neutron star. It's an easy shorthand for the most part, since we're not 'we…

> A scale would tell you that you weigh[] slightly less at the top of a mountain than at sea level, though in reality you'd have the same mass.

For an illustration of a pedantic distinction, this seems awfully unlikely to be correct. You gain mass by eating and drinking and lose it by urinating, defecating, and breathing; odds are you're not going to have the same mass on the mountaintop.

Re: How Raganwald Lost His Crown

#26

Post by platz »

braythwayt wrote: post #23
bloat wrote: post #22

Earlier quoted context omitted.

I was going to jump in and say that the pound is also a unit of mass. But it turns out its both. https://en.wikipedia.org/wiki/Pound_(force) https://en.wikipedia.org/wiki/Pound_(mass)

And then there's the foot-pound, a unit of torque much prized by the owners of muscle cars until eclectric vehicles went from obscure to early-adopter status.

Also, assuming we're talking about rest mass, since without that distinction the word mass is ambiguous in accelerated contexts.

Re: How Raganwald Lost His Crown

#27

Post by StavrosK »

thaumasiotes wrote: post #25
WaxProlix wrote: post #18

Earlier quoted context omitted.

They roughly infer their mass (in kilograms) by assuming 9.8m/s/s gravitational acceleration and using a scale to judge how much mass the resulting 'push' would require given that pull. A scale would tell you that you weight slightly less at the top of a mountain than at sea level, though in reality you'd have the same mass. Same is true on a neutron star. It's an easy shorthand for the most part, since we're not 'we…

> A scale would tell you that you weigh[] slightly less at the top of a mountain than at sea level, though in reality you'd have the same mass. For an illustration of a pedantic distinction, this seems awfully unlikely to be correct. You gain mass by eating and drinking and lose it by urinating, defecating, and breathing; odds are you're not going to have the same mass on the mountaintop.

This is physics, we're clearly assuming a perfectly spherical human with lossless and instantaneous modes of travel.

Re: How Raganwald Lost His Crown

#28

Post by ricardobeat »

WaxProlix wrote: post #14
braythwayt wrote: post #2

Disclosure: A rare self-post. I'd be very grateful for any and all corrections to the story, as I am far from an expert is astrophysics, geology, or pretty-much anything else.

> I would have found that while my scale tells me that I am about 86 kilograms on Earth, I would have weighed 8.6 trillion kilograms on this neutron star. Kilograms are a measure of mass, not weight. Pounds would be a more appropriate unit there.

A pound is also a measure of mass [1]. Unless you're thinking of the 'pound-force' which is just the force of gravity applied to one pound-mass. The same definition exists for kilograms (kilogram-force) but is not part of the international unit system. Gravity is slightly different close to the poles etc so a *-force unit will never be precise in this context.

The majority of humanity has absolutely no idea what 'one pound' is when not referring to the currency, and will merrily say they weigh X kilograms.

[1] https://en.m.wikipedia.org/wiki/Pound_(mass)

Re: How Raganwald Lost His Crown

#29

Post by dredmorbius »

Thought: Isaac Newton was an alchemist. He was looking for the secret, most especially, of transmuting base elements into gold.

Instead, he discovered the law of gravity.

Which, as expressed in neutron star formation and collisions, is what transmutes base elements into gold.

Score one for the alchemists.

Re: How Raganwald Lost His Crown

#30

Post by gumby »

saagarjha wrote: post #24

> I might have lifted my Apple Watch and said “Hey Siri, record a note.” If I was using the Apple Neutron Star Edition Apple WatchOS, it would have had to correct for time dilation between time at my waist and time at my shoulder. Would it, really? Using a back-of-the-envelope calculation using a formula pulled from Wikipedia[1], and assuming: 1. The Apple Watch needs to stay within 50 milliseconds as Apple advertise…

> should take a couple hundred seconds before Apple Watch drifts out of sync. Should be long enough for Siri to record your note :)

I wouldn’t be so sure. First of all, siri is pretty slow already in the best of times. Second, the watch doesn’t do the recognition onboard; it sends the audio (or some processed version, I don’t know) to your phone. And a neutron Star, especially a spinning one with lots of junk around it, we be generation an ENORMOUS amount of RF interference. I can definitely see it getting out of sync.

Then again it (and you) are not really rated for neutron sta4 conditions and the tidal forces would definitely tear you apart; just moving your arm would distort the watch, 7nless perhaps you purchased the extra expensive ceramic version.

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