Seemingly trivial things that intrigue you
Comments
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I think you are missing a factor. The body is only 25% efficient in converting energy, so it would take 800kCal to put out 200W per hour. I don't have a power meter, but that sounds more likely as I doubt I was putting out 200W. My ride was just under an hour.
I think burning 1000+ calories/hour is a good workout. Yesterday didn't feel like that although if I had done the same distance in the same time on my mountain bike, I would have felt much more tired and the online calculator didn't have this as an input.
The problem is that in 25 mins on a treadmill, I can burn 500+ calories, so my biking seems to be way to efficient given that the primary purpose was fitness.
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Just wondering if I'm going to have to reconsider the partial retirement now.
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Have you tried shopping around? 😂
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Mmm,.you are right. Just googled and some activities are more like 50% efficient, because of the return of potential energy from tendons. Cycling won't be that high, but perhaps higher than 25%.
Hard to say what your treadmill is telling you. There will be a whole host of assumptions to get from heart rate to power, but you are trying to compare two very imprecise measurements, I think.
Fwiw I think 1000 kcal per hour would be a stroke inducing effort at any sport. This based on some non rigourous use of Google.
This table seems to be quite widely used.
https://www.dhs.wisconsin.gov/publications/p4/p40109.pdf
No idea where it comes from. It's probably referenced in the article.
Seems more or less that whatever you are doing, it comes out more or less the same depending on effort level. I find that I can cycle for a lot longer than I can row, but that it is a lot harder to row as gently as I can cycle.
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I'm fine with the treadmill measurement. Everything is consistent - heart rate monitor, treadmill and online calculator all produce the same results. This is perhaps not that surprising as there aren't as many variables
Cycling seems to have more variables.
I certainly couldn't keep up my treadmill pace for an hour, so that is consistent with your rowing. I guess it should be possible for me to ride a bike really hard, but I think my brain stops me.
Also with regard to calories per hour. It's very weight dependant, so in your chart running and cycling at vaguely quick speeds get there for a 190lb person and it is possible to be heavier than that! I was only giving it as a comparison.
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The issue I have with cycling hard is that I do it for fun. And it stops being fun if I'm too exhausted for too long.
Whereas on a rowing machine it's just exercise.
In a boat there is also the need to be alert enough to avoid drowning, which puts a bit of a safety limit on things.
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I use a rule of thumb that running 1 mile equals 100kcal. Seems to work when I try to balance calories in and out to lose weight but is obviously very basic. My thinking is if I run a 7 minute mile it's shorter but higher intensity than a 10 minute mile. I doubt it would qualify as a scientific approach though! Cycling is far harder to judge for me as I don't use a power meter other than on the turbo.
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I’ve been cycling past an aggressive farm dog for years, and often take an alterative route to avoid him when I’m not feeling so lucky. This mastiff type dog has a bark to match his mean looks.
Driving that road recently, I spotted ‘Cujo’ at a distance, trotting back towards the farm. He was carrying something large in his jaws. Getting closer, Cujo stepped into the verge to let me drive past. Now I could see what he was carrying…the hind quarters of a *@#%ing sheep, wool, blood, hoof and all.
A kill or scavenged? I’ve been going the alternative route (on the bike) more often.
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"Oh 'e'd never 'urt nowun".
1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
Pinnacle Monzonite
Part of the anti-growth coalition0 -
Those scrolly date things you need to use on phone Apps. Ultimately extremely annoying. Always. But today I was trying to register a new banking app and for date of birth it would allow me to scroll forward years and years into the future. Maybe I can be like Minority Report and do Future Crime or Future Fraud then absolutely deny it was me as I could have been dead at that time....
Sometimes. Maybe. Possibly.
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I've heard that a few times...never get reassured.
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I mean, they are hunting animals. It's always a possibility however soppy it is most of the time.
1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
Pinnacle Monzonite
Part of the anti-growth coalition0 -
It's depressing how far down I have to scroll now. Not quite as far as 69 though😃.
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...now, now children. 😂
The above may be fact, or fiction, I may be serious, I may be jesting.
I am not sure. You have no chance.Veronese68 wrote:PB is the most sensible person on here.1 -
When I say not quite, I really do mean it.
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I get abuse for being old by a friend that's exactly 3 months younger than me, so I'll gladly abuse those younger than me, even it is jealousy and bitterness 🙃
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You can tell your friend from me, he's an old f#cker.
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Suffering badly from split skin around nail folds and finger tips from Chemo treatment. Been trying all kinds of moisturisers. Some better than others but none that great.
I though I'd give my tube of Chamois Butt'r a try. Its amazing! Best thing I've used so far. So not just for arseholes then.
Sometimes. Maybe. Possibly.
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Full USB sticks weigh less after you add data than when they are new.
By a really tiny amount, but still.
1985 Mercian King of Mercia - work in progress (Hah! Who am I kidding?)
Pinnacle Monzonite
Part of the anti-growth coalition0 -
That's got to be factoid of the week.
Will see if I can figure out why.... Think it just be just that the free energy change is negative, meaning the alignment of magnetic domains is exothermic and exceeds TdS (entropy).
Unless adding data increases entropy...
Help. I'm just a chemist.
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Maybe they weigh less because more electrons are wobbling.
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I always thought they weighed more.
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Well, 'lectrons it is.
"Believe it or not, they get lighter. USB drives use Flash memory, which means the the ones and zeros of your data are stored on transistors.
When you save data, a binary zero is set by charging the float gate of the transistor, and a binary one is set by removing the charge.
To charge it, we add electrons, and the mass of each electron is 0.00000000000000000000000000091 grams.
This means that an empty USB drive (which mostly holds zeros) weighs more than a full USB drive (which has ones and zeros). Add data, reduce the weight.
However, you would need to weigh more USB drives than exist on the planet together at once before the difference in weight became easily measurable."
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That doesn't make sense because the entire USB stick would then carry a static charge, and static charges tend to be transient.
Can that be right?
Suspect that there is charge balancing elsewhere in the system. And that the mass change is an energetic effect.
But I was wrong once before.
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Google Gemini:
AI Overview
Yes, a hard disk drive (HDD) weighs more when data is added, but only indirectly:
- Electronic storage
- Adding data to electronic storage, like RAM, SSDs, and flash memory, increases its weight because it requires storing an electric charge. Each electron has a very small weight, so adding electrons adds a tiny amount of weight. For example, 1 GB of flash memory filled with 1s weighs more than the same memory filled with zeros.
- Magnetic HDDs
- An actively in-use HDD weighs more than an inert HDD due to side effects of adding the data. The mass difference is very small, at the level of 10-14 grams.
- Stored data bytes
- A stored data byte has a physical weight, but it's very small, around 1 attogram, which is one-quintillionth of a gram.
Some say neither lighter nor heavier.
Quote from above: 'The mass difference is very small, at the level of 10-14 grams.'
!4 grams, surely not.
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That's also got enough nonsense in it to be worth ignoring. A hard drive is not 14g heavier when it is full.
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Yup I've just done some googling based on what I want the answer to be, and it turns out that's the answer. There are local charge imbalances by which data is stored, but the overall charge of the device is neutral. The effect on mass is thus not that you can somehow inject or remove electrons, like the semiconductor is a bucket of electrons. That's not how bad theory works.
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