swansont

Be warned that there are some engineering treatments where the term "reaction force" is used incorrectly. I noticed this in a recent thread about action/reaction force pairs. They won't work where Newton tells you they won't. Newton explains that an object in uniform motion maintains that state unless acted upon by a net force. If you are in a situation where that is not the case (e.g. a rotating frame) then you can't expect the other laws to apply.

It came from the same IP address as another of your accounts, and just a few months after that account was banned. Quite the coincidence.

Here are some numbers. A calorie of food is actually a kilocalorie of energy, and there are 4.18 J per calorie. But the human body is only around 25% efficient at converting food to work (the rest is shed as heat), so a calorie consumed gets you about a joule of work. You have a baseline of consumption required just to breath have your heart pump, and move around a bit. Any work extracted has to be on top of that. 600 Calories consumed ( a moderately-sized meal; a Big Mac with a few french fries) allow one to output about 600 kJ of mechanical work. You could imagine getting on a stationary bicycle and doing work at a rate of 100W (enough to light up a few light bulbs — back in the day this would be a single incandescent bulb, but we have more efficient lights now), so you'd be doing this for 100 minutes. That's a pretty good workout. But if we think in terms of usable electric power, 1 kWh is 3600 kJ (1 kJ/s *3600 s), and you've only produced 1/6 of that. It's not a lot of energy. You might pay $0.15 for a kWh of electricity, but you paid several dollars for that Big Mac, and if you want to produce a kWh you have to do that for 10 hours (600 minutes) It's not economically feasible, and just not possible. The above is just to keep a few lights on. How many people to run a whole household? The US average household power consumption is around 29 kWh each day, You'd need multiple people on bikes, doing this in shifts. We use more power than we could generate on our own. The CO2 analysis (getting that food made and delivered) would be more bad news, but it's going to be far cheaper to use other energy conversion methods and deal with the CO2 than to use human power. Thousands of years ago we got away from human power for a reason — animals generate more power, and machines generate even more. You can't have anything like a modern lifestyle using human power.

Is there a point to simply re-posting this, without regard to the previous comments? Can you discuss the energy demands of human-powered devices at all?

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If FA is up, what force is there keeping the screw from accelerating upward? What force causes MT to move? Everybody has noticed. But here's the thing: you could simply define your system to include fewer components "inside the box" i.e. internal vs external is an artificial constraint you put on the system. Where does the violation of the third law occur? Analyze just that interaction, and get rid of the extraneous discussion. Make that the system. But here's the conundrum: that means Newton's 3rd law would apply. IOW, Newton's law doesn't cease to apply simply because you put something in a box. If you think that's the case, it's most likely because you aren't accounting for some force introduced when you make the system more complicated. (this is nothing new; it happens all the time in relativity discussions with people who have decided that relativity isn't correct.) No, not then either. As above, if you think that's the case then you just haven't accounted for some interaction. A standing wave of what? Is this an EM standing wave? "Apply a phase shift" isn't magic. There has to be an interaction between the particle and the EM wave. That interaction is what moves the particle. That's not what dm refers to with Newton's laws. dm is the change in mass of the system, but you've define the mass of the system as a constant.

Not seeing how mT can correspond to dm/dt Is the mass being ejected?

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! Moderator Note This thread is not the place to discuss writing code, or anything related to that. Plus the transgressions of the original account, Achilles. And all of the subsequent sockpuppetry.

Not helpful if they aren’t identified in a diagram. That’s not in compliance with rule 2.7. Discussion needs to take place here, without requiring people to click on links. Internal forces don’t cause motion of the CoM. Action and reaction forces act on different objects What is an “induced” force? That’s what you should be deriving here

Or just that it's a huge security risk, full stop.

It's possible there are state-level sealed indictments, and folks are waiting until the moment he isn't president anymore, so they can arrest him.

I have read an observation that what Trump reported to the IRS (losing money) may be markedly different than what he reported to banks (business is great, lots of assets) in order to get loans. If so, he could be in big trouble for fraud.

! Moderator Note From rule 2.7 (emphasis added) Advertising and spam is prohibited. We don't mind if you put a link to your noncommercial site (e.g. a blog) in your signature and/or profile, but don't go around making threads to advertise it.

Who were you?

https://www.nytimes.com/interactive/2020/09/27/us/donald-trump-taxes.html

I agree with iNow that there is no point; Schumer has indicated that the dems will unleash all of the delaying tactics at their disposal, to make things as uncomfortable as possible.

! Moderator Note Moved to math. Kindly make an effort to post in the proper area, rather than dumping threads in the lounge

This kind of artifact - as seems likely - is known as a lens flare.

! Moderator Note Post merged with thus thread. Please don’t hijack other threads with this subject matter

You have not adequately labeled you diagrams and described your variables. r⃗ A≠r⃗ R⇒τ⃗ A≠0⃗ and τ⃗ R≠0⃗ To start: what are rA and rR ?

Bad teams are a failure that traces back to human failings; it’s not inherent to teamwork. Any project of sufficient complexity will be compromised by having just one worker. Wider range of expertise applied to the project and the ability to work in parallel are two important advantages teamwork affords.

You presented hypotheses on Planetary Axial Tilt and Gas Giant Ring Formation and Orientation. Not living beings. That’s not an equation with sufficient predictive or explanatory power. Partly because you haven’t defined core strength, or established that axial tilt can “charge” anything. Neither hypothesis is biology. Do your models depend on how the planets move? (the sun does not move with an ion drive) What’s your evidence for this claim? Not living, and unless you can point to where this topic appears in mainstream physics, here is where it will stay. Yes, our rules. Honest discussion includes you not tap-dancing about how you can’t provide a mathematical model

Finding comparisons isn’t hard https://www2.palomar.edu/anthro/hominid/australo_2.htm https://www2.palomar.edu/anthro/homo/homo_1.htm Look at the pelvis, cranium and jaw. africanus has distinct differences with both modern humans and other modern ape

“When he arrives” is ambiguous Is he moving, or has he come to a stop wrt earth? If moving, he measures the distance to X as contracted. If stopped, he measures what the earth observer measures The answers won’t change from asking the same thing over and over