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Cooperative Global Weight Loss

Use the world as a giant treadmill.
 
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OK, so every action has an equal & opposite reaction right? so if everyone on the planet runs counter to the spin of the earth we should be able to speed it up.

Centripetal force counters gravity so if it spins faster everyone will weigh less.

Burn fat & lose weight increasing the worlds spin, lose more weight from that.

Fantastic! double results for the effort.

What could possibly go wrong.

Skewed, Oct 11 2019

World Wave World-wave
[2 fries shy of a happy meal, Oct 12 2019]

Funny hamsters in wheel videos https://www.youtube...watch?v=X1kcTdzKb_E
YouTube [Skewed, Oct 15 2019]

[link]






       //so if everyone on the planet runs counter to the spin of the earth we should be able to speed it up// The effect will be proportional to the mass of the person running. So, we should just get all the really fat people to do this. The rest of us can watch, take photos, post videos on Youtube and so forth.
MaxwellBuchanan, Oct 11 2019
  

       Can you film some prototyping on a standard treadmill for us?
wjt, Oct 12 2019
  

       You don't need to run, just hop, tap the gas, or the brake depending on your direction of travel when the wave passes. [link]   

       What happens when you reach Atlantic City?
RayfordSteele, Oct 12 2019
  

       We're going to have to build a really long bridge.
Skewed, Oct 12 2019
  

       What happens when they stop? Or do they have to keep going forever?
Frankx, Oct 14 2019
  

       Think about angular momentum. Taking Earth and all it’s people as a closed system (that is, ignoring things coming from/going to outside the atmosphere), angular momentum is conserved. So running people/accelerating/braking cars, anything that starts “from rest” and returns “to rest” (at the same height) won’t have a net effect on spin speed.   

       If you had a large elevated mass, and redistributed it at a lower elevation, that would have an effect. So if you bulldozed the Himalayas and tipped the rock into the Marianas Trench, you would actually increase the spin of the earth.
Frankx, Oct 14 2019
  

       //if you bulldozed the Himalayas and tipped the rock into the Marianas Trench, you would actually increase the spin of the earth// - I'm happy for you to try this to test your theory, but I'm not certain it'll work. When the Himalayas are pushed into the Marianas trench, you're right that you're moving mass closer to the Earth's centre of rotation, but at the same time, you'll also be moving the mass of displaced water away from the centre of rotation (as will be seen in the raised sea levels and concomitant wiping out of coastal cities around the world and huge loss of life).
hippo, Oct 14 2019
  

       //What happens when they stop?//   

       They don't.   

       That's why we need a really long bridge, at least two.   

       You can't turn around & walk back the way you came, equal & opposite reaction remember, to get back to where you started while avoiding cancelling out any extra spin you achieved you have to go all the way around.
Skewed, Oct 14 2019
  

       //you'll also be moving the mass of displaced water//   

       Stone is denser than water, it's why it sinks, so less weight gets displaced up, which means?
Skewed, Oct 14 2019
  

       //which means// ...the total moment of inertia has reduced, so angular velocity increases to conserve angular momentum.
Frankx, Oct 14 2019
  

       //What happens when they stop?//   

       This is the problem, you only get an effect while people are accelerating up to speed. Perhaps if they were vaporized by a large laser once they attained Vmax?
bs0u0155, Oct 14 2019
  

       No they can stop, they just can't turn around & walk back.
Skewed, Oct 14 2019
  

       // //which means// ...the total moment of inertia has reduced, so angular velocity increases to conserve angular momentum.// - yes you're right, it would work. We need to do this anyway, to counteract the gradual slowing down of the Earth's rotation caused by tidal drag from the moon.
hippo, Oct 14 2019
  

       //Perhaps if they were vaporized by a large laser// the vapour would slow down and so there would be no net advantage to this action.
pocmloc, Oct 14 2019
  

       //vapour would slow// ahem //No they can stop, they just can't turn around & walk back.//
Skewed, Oct 14 2019
  

       //they can stop// ...no, it’s the force they exert while accelerating that adds to the rotational speed. If they stop, the deceleration (reaction force) undoes that. Even if they turn North (say), or are blasted to atoms by a laser - if their mass is decelerated within the Earth-atmosphere inertial system, it undoes the gain from accelerating in the first place.   

       So they have to keep running west, keep on running... forever.   

       Pink Floyd “you run and you run to catch up with the sun but it’s sinking...”
Frankx, Oct 14 2019
  

       One of the problems with this idea is that the entire point if losing weight is that other people are not.
sninctown, Oct 15 2019
  

       Actually, I’ve just realised that rocket launches to orbit are stealing our angular momentum. They often launch eastward to take advantage of the earth’s spin. By doing that, they slow down the rotation. We’ll get it back again if/when they de-orbit, but still! NASA has made our days longer!
Frankx, Oct 15 2019
  

       //it’s the force they exert while accelerating//   

       Um no, either you're yanking my chain, having a senior moment, or I am.   

       It's the force they exert while 'moving', every step exerts a force, not taking another step doesn't cancel that force, you have a football in space, you push it away from you (& you away from it) with your foot.. does it ever stop moving away from you.   

       Think a hamster in its wheel running as fast as it can then it stops, if you were right the wheel will stop dead when the hamster does.   

       It doesn't [linky] 1:14 is one of the best.   

       The wheel slows & eventually stops due to friction in the bearing (& air of course) but not because the hamster stopped running.
Skewed, Oct 15 2019
  

       //having a senior moment// If your hamster wheel was in space, the wheel would spin only while the hamster walked. On earth, the wheel gains additional motion as the hamster climbs the sides of the wheel, and its additional potential energy is converted by gravity into kinetic energy. Given a heavy enough wheel, some of that energy goes into its intertia - which would keep it rotating if you vapourised the hamster. But in space, without that free input of gravitational energy, the hamster and the wheel must exert equal and opposite forces on one another that cancel out.   

       Imagine walking on a playground roundabout rotating on a perfectly frictionless spindle. Without touching the floor, your intended motion clockwise ought to be equally and oppositely counteracted by the roundabout's motion anti- clockwise. If you stop walking, then the roundabout should also come to a stop beneath you and you'll remain exactly where you started.   

       If there's any residual motion then the laws of thermodynamics will have been violated, and you'll be on the money for inventing some kind of perpetual motion/energy device.   

       Otherwise, you'd be able to "swim" in space by waggling your arms about to conjure up free motion.
zen_tom, Oct 15 2019
  

       //If your hamster wheel was in space, the wheel would spin only while the hamster walked// - I think the wheel and hamster would rotate in opposite directions around their combined centre of mass, which would look slightly different to the wheel spinning around its axis.
hippo, Oct 15 2019
  

       //yanking my chain//   

       No, really not! Sorry if it seemed like that.   

       Here's a different way of looking at it:   

       You have a 100kg mass on a level frictionless track (in a vacuum) pointing west. There's a big spring that will accelerate the mass at 10m/s^2 for 1s.   

       The fixed end of the spring is attached firmly (through some structure) to the ground.   

       When you release the spring, a force of (100*10) = 1000N acts on the mass accelerating it, and a reaction of 1000N acts (through the structure) on the ground - for 1 s.   

       The mass travels along the frictionless track at 10m/s for as long as you like - and then it hits a buffer at the other end, where it's brought to a stop at 10m/s^2. The buffer is attached to the ground, and again exerts 1000N, for 1s   

       Between those two points, the mass exerts no east-west force on the earth. When it's launched, it applies a force to the planet, accelerating the spin very slightly. When it reaches the buffer, it applies the opposite force, slowing the planet's spin back to exactly it's original speed.   

       The reason your feet continue to exert backward force when you're running at a constant speed is to overcome air friction (and creaky joints in my case).
Frankx, Oct 15 2019
  

       I think [hippo]'s got me, your's is longer so I've not skimmed it yet. Dang! Remember I did say //or I am// about that senior moment option. I'm going to have drag up some YouTube & Wikipedia to satisfy myself where (if, I think it may have) my mind failed me now.
Skewed, Oct 15 2019
  

       //No, really not! Sorry if it seemed like that//   

       Don't be (unless you are ;p) my senior moments aren't your fault.
Skewed, Oct 15 2019
  
      
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