Something Random

Handruin said:
Thanks to ddrueding I'm reading about physics to understand how much energy is required to spin a 20-ton mass object to 20K RPM in a vacuum. I never took any kind of physics so I'd like to learn how to calculate this. I have to assume zero friction for the rough estimate. With friction, would it just be like adding a fluctuating and variable weight to the mass? Then the friction will likely generate heat which would then change things ever so slightly over time. Maybe that heat from friction is exchanged through liquid and also used to reclaim energy since the energy going in is converted to both the spinning object mass and also friction based heat? Maybe the bearing is liquid cooled and that heat can be used for your house during the exchange process?
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This should help you a little bit.
http://galileo.phys.virginia.edu/classes/635.stt.summer05/Manual/July 20/Rotational Dynamics.pdf
http://en.wikipedia.org/wiki/Rotation_around_a_fixed_axis

The topic you are looking for is rotational dynamics. To account for friction, either bearing or air, you add th effect of friction into the force equations.
 
Wow, that one spins at 52K RPM and weighs 53 LBs. That doesn't seem like it would work for David. The output is 12 seconds at 200KW. That to me seems like a temporary outage during changeover to a generator perhaps.
 
Thanks for the links Howell, I will take a look at them. I noticed that the unit you linked to said it had no mechanical bearings and that it used magnetic levitation. For David's idea, it would take a considerable magnet to hold 20-tons which would use considerable energy.
 
Handruin said:
Wow, that one spins at 52K RPM and weighs 53 LBs. That doesn't seem like it would work for David. The output is 12 seconds at 200KW. That to me seems like a temporary outage during changeover to a generator perhaps.
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You are exactly right about what this is designed for. Battery packs for the same purpose require regular repurchasing but this solves that problem.
 
Handruin said:
Thanks for the links Howell, I will take a look at them. I noticed that the unit you linked to said it had no mechanical bearings and that it used magnetic levitation. For David's idea, it would take a considerable magnet to hold 20-tons which would use considerable energy.
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And you still have to have significant foundational support for the base.
 
It is discontinued for some reason. Maybe 12 sec. is insufficient for all the generators to start each time. I don't know what we have at work, but sometimes the generator turns on outside.
 
The trailers for Battle: Los Angeles are all supremely awesome, especially the third one. Why had I not heard of this movie?
 
Erm, no. Not really. Though I will be taking next Tues. morning off to service my car. Of course, I will have a pair of laptops, a pair of phones, and a pair of hotspots, just in case.

My last vacation was my honeymoon 2 years+ ago.
 
Chalk one up to Newegg's inconsistent packaging. At least this time they seem to have gone overboard. I ordered 2 2.5" HD's. Here's how they came packaged. Each one was wrapped in bubble wrap and put in it's own box. Those two boxes were surrounded with packing paper in a much larger box.

newegghddpackaging.jpg
 
How many posts is enough? If I have 18,000+ posts, should I continue to 20K? What is the most number of posts that you have on any forum?
 
I don't recall the forum off the top of my head, but I saw someone with >50k posts on a forum not too long ago. I'm inclined to to believe it wasn't from someone editing the backend database to bump their post count either.
 
Yeah. I don't remember how many before that. I started there not long after SR started, though I don't remember my number, so there were probably quite a few then as well.
 
Well, I have 7425 at AVSforum. I have 2400 on Hardforum. I have 3821 on Genmay. I had >4000 on AV123's forum before they assumed room temp. I have 1610 on Maxima.org. I don't recall how many I had on SR. I think most other forums I'm under 1k.
 
Come to think of it, most forums don't last very long. I've been posting for 12-13 years and the majority of sites no longer exist or the forums were recreated. I've probably lost over 5K of posts in 8 forums, that is not including the MBF. I'm only active on 2-3 forums now. :(
 
LunarMist said:
Come to think of it, most forums don't last very long. I've been posting for 12-13 years and the majority of sites no longer exist or the forums were recreated. I've probably lost over 5K of posts in 8 forums, that is not including the MBF. I'm only active on 2-3 forums now. :(
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Well one cause of that problem was when a lot of boards were first hosted on the ancient subscription services before vB and others came about. Some either transitioned off, lost members and died or were just forgotten. right now I am pretty active (say 100+ posts) on about 10 forums, with more than half of those relating to a certain product. One is for my car, another is oriented to the computer I own, and the others are some I frequent that kind of cover all the stuff I like to talk about. SomethingAwful is a one that has been around for a loooong time that I don't see going anywhere anytime soon. I think my post count is above 10,000 there :drinka:
 
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