Why kinetic energy does not equal 0.5MS^2

[seasnake]

0.5 S^2 = 2 sum of all (Ad) + (So)^2.

 

currently accepted Ke = 0.5MS^2

 

where: S = speed, or velocity; A = acceleration; d = interval distance; So = initial speed = speed at time zero; M = mass; and Ke = kinetic energy

 

Adding all kinetic energy values on a moment by moment bases differs from kinetic energy calculated during the same amount of time, i.e. the sum of parts does not equal the whole by the currently accepted kinetic energy formula as any change in the value of any variable during the passage of time will mathematically result in a discrepancy due to the improper multiplication of mass. Simply multiplying mass to 0.5 velocity squared is bad math as it is a violation of relativity.

 

Explained in an example, if 60 seconds equals an hour, the sum of all seconds divided by 60 should equal how many hours have passed. If it doesn't, the sum of all parts (seconds in this example) will not equal the amount of hours that have passed and relativity between seconds and hours is violated.

 

0.5MS^2 calculated on a per second bases, added up, and converted to hours, does not equal 0.5MS^2 calculated on a per hour basis, as mass for any object in motion, existence, is not a constant (motion results from energy that is being used, all objects in existence have molecular half-lives).

 

[edit]Blatant plug for own book removed by Buffy[/edit]

 

Copyright 2007; Adam Pellegrino: all rights reserved.

[Buffy]

Please tell us why we should care?

 

Note that we frown on people barging in and using this site for free advertising and publicity. If we find you're not Adam Pelligrino himself, the copyrighted content will be removed.

 

This is a place for discussion, not pontification. If you don't start an actual discussion here, the entire thread is likely to be removed.

 

So, tell us, what are you trying to say?

 

Thank you for your cooperation,

Buffy

[snoopy]

Hello seasnake,

 

A lot of what you are saying doesnt make much sense. The newtonian equation for kinetic energy doesnt work in relativistic situations and you have to use einsteins equation for kinetic energy

an explantion can be found here

en.wikipedia.org/wiki/Relativistic_mass

but for everyday objects newtons equation is fine its only a problem for small fast moving objects.

 

(sorry I couldnt post the full link as I have to reach a post count of ten before im allowed to do that)

[Farsight]

I'm sorry seasnake, but it does. I've thought long and hard about this. The reason it's ½mv² is because there's an integral here. That's what kinetic energy is all about. Read ENERGY EXPLAINED v2.1 and check out this excerpt:

 

Consider a 10 kilogram cannonball, in space, travelling at 1000 metres per second. We talk about how much kinetic energy this cannonball has. We talk about KE=½mv² and we do the maths and get five million Joules. But what has the cannonball really got? Its mass seems real enough, I hefted it into my spaceship this morning before I took off. And its motion seems real enough too, because one false move and it’ll be smashing through my viewscreen taking my head off. To find out more, I take a spacewalk to place a thousand sheets of cardboard in the path of my cannonball. Each sheet of cardboard exerts a small braking force, slowing the cannonball to a halt. This takes two seconds. We know that the cannonball will punch through more cardboard in the first second than in the second second, because it’s slowing down. So we deduce that a cannonball travelling at 1000m/s has more than twice the kinetic energy of one travelling at 500m/s. We can do the arithmetic for each second, then slice the seconds up finer and finer, and we end up realising that the ½v² is the integral of all the velocities between v and 0. But what we don’t realise is that kinetic energy is a way of describing the stopping distance for a given force applied to a given mass moving at a given velocity. You can flip it around to think about force times distance to get something moving. Or you can think in terms of damage. But basically that cannonball has “got” kinetic energy like it has “got” stopping distance.

 

It’s similar with momentum. That’s a different way of looking at the mass and the motion, based on force and time instead of distance or damage. We look back to our cannonball and cardboard, and we know by definition that in the first second the same amount of time passed as in the second second. So we realise that a cannonball travelling at 1000m/s has twice the momentum of one travelling at 500m/s. But what we don’t realise is that momentum is a way of describing the stopping time for a given force applied to a given mass moving at a given velocity. A cannonball has “got” momentum like it has “got” stopping time.

[Jay-qu]

Hes right, it doesnt equal 1/2 M v^2 - that is non-relativistic Kinetic energy but is a perfectly good approximation for values <<c.

[ErlyRisa]

what's the big deal....I thought this was common knowledge.

 

--but it's still a perfectly fine formula for everyday tasks....just like quantum physics is a perfectly fine approximation for the observation of elemental interiors.

 

...what would be an interesting formula is...

 

E= m(v1-v2)^2 ....yes we could use Einstein equations ---but why bother.