Sorry, v**3 not gonna bite. I'm not claiming I can predict the benefits of lighter shoes. I'm claiming you can't. Or at least that you can't using the equation you offered because that equation bears no connection to actual physics. (other than as a parody).You claimed:"mass changes ( we are talking small, not losing muscle ) with speed, are a cubic dependency"and as a rationalization you cited a reference on Drag Power.But drag is not dependent on the mass of the object experiencing the drag. (please check the equation you cited if you aren't clear on this)Two objects moving the same speed through the same fluid with the same shape experience the same drag even if they have dramatically different weights. Adding a weight belt to a runner will not appreciably change the drag they experience.Then you tried to make some hand waving argument where you state the equation for kinetic energy and somehow think you can add an extra factor of v to represent the drag. But drag is a force, not an energy. You can't just magically multiple forces times energies and imagine it means something. And even if you *could* do that you've done it wrong since drag scales with the square of v, not linear with v (again see the drag equation you initially cited). So after magically multiplying the (wrong) velocity scaling of drag force by kinetic energy You say:force exerted = 0.5mv^3But this isn't a force (multiplying a force times an energy never is). It has units like kg(m/s)**3. That's not a force. Remember Newton. He came up with clever things like F=mawhich means force units look like kg*m/s/sDo you see how those aren't the same?And even if that equation represents something real it *still* doesn't support your initial calculations where you were taking the cube of the mass. The equation you've magically derived is linear (not cubic) in mass. I don't claim to be able to predict the effect of lighter shoes on running performance (the article Northern Star cites would be a good place to look if you actually want to learn more about that). But I can recognize bogus physics logic. That is what you've presented. It isn't that you've made a single mistake. It's that ever single step is independently wrong and inconsistent with your other statements. Even if you were inventing your own set of physical laws the calculations you've made and the arguments you claim support them don't even make sense with each other, much less bear any relation to reality.You are some sort of anti-physicist. I applaud you.
ventolin^3 wrote:
ordersofmagnitude wrote:Wow, this is wrong in so many ways I don't even know where to start. It's like a study in the sort of pseudo-physics answers I've seen on exams from intro physics classes.It's airplanes taking off from treadmills sort of logic. I really hope you're just trolling here and don't actually believe any of this.
If so I suggest you return to an intro physics text (if you've ever read one) and reconsider your understanding of the difference between force and energy
you have posted copious amounts of drivel without hard numbers
impress me :
"a 60kg guy wearing a smooth-fitting, unimpeding 1kg belt around his waist runs a M in
2"05'00.00
what coud he have run for it without the belt ???"