Roll on the 20th June

[spinner]

What about a NASA satellite that passes near enough a planet to accelerate & then slingshots away.

I'm not trying to be a jerk, I'm really curious as to what happens there. That seems a little closer to what we're trying to do than the actual collision.

"Gravitational slingshot" is widely used concept in Space exploration, which enables our artificial satellites to accelerate on behalf of rotational and inertial momentum of the planet, which satellite is passing by...
So, energy is stolen from the kinetic energy of that planet.
Nobody worries, because it is the same as stealing a drop of water from all the oceans on Earth...
Cheers!

[BATMAN]

BATMAN ....HI ALL

HERE IS A PIC OF ONE OF THE BAT WHEEL'S 

I WILL POST VIDEO'S UP ON THE WEEK OF AUG. 10 2008

I HAVE TO GO OUT OF TOWN.

HAVE FUN....................BATMAN.

[purepower]

@ Exx

You don't get it, do you?

I did thank you for defending be back when ago. To return the favor, I have refrained from putting you in your place in regards this banker energy bit and just let it slide off as childish ignorance. Quit trying to play "engineer," you are losing badly.

Nobody cares what you have to say about me. Stop wasting webspace.



@ALL

Show of hands, who wants to see more posts of Exx insulting me, or me insulting Exx?

Who wants to see the banked energy debate continue?


@ Mr M

That's the bit I'm not interested in weirdly enough...

I'm not looking for a way to create a perpetual motion magnetic wheel or other device like that, I'm  looking to understand where energy comes from, where it ultimately goes to, how it changes state and how modern day science measures it all.

I'm not looking to poke holes in science... Just trying to poke knowledge in to my scientific holes (ooer).

What I actually want to know is if the input energy in my scenario is measurable and quantifiable, all of the different types of output energy are measurable and quantifiable and the sum of the output energy is exactly equal to the input energy based entirely on the gathered data...

I know that I'm supposed to know that they are equal but I want to know how I can indisputably know that this is the case... Urgh, I'm either coming off as a complete village idiot here or I'm not explaining myself well... Maybe both.

I'm a coder by trade and, a little chest puff here, I know how to write in upwards of fifteen languages... I can also pick up new languages and see comparable functions, structure and syntax which allows me to learn new languages very quickly. 

When I write an algorithm I know the variable(s) passed in, what work is done and what variable(s) are returned. When I look at my scenario I don't know what goes in, what happens and what comes out as a result and I'm trying to improve my knowledge...  I understand a lot of what comes out like heat, deformation, sound and how these propagate in various media but I don't know everything by a long way and as it is generally accepted that the energy in is always equal to the energy out then it must be possible for me to get the information I want.

For example... If it is possible for someone to say "Energy In = Energy out" then it should be possible to express that perfectly in a far more complex manner and that information should be available somewhere in one easy to flick through document. Any scenario which is even remotely like mine, any at all providing it accounts for all inputs, all outputs and what happens during the conversion of the energy... Bah! *slap slap slap self*

I'm being an idiot actually... It happens.

I'll go read t'internet some more, I know what I want is available it's just not in the 'Idiots guide to reality'.

All great thoughts and questions.

To answer your CoE question, yes.

If we were to measure your input energy, subtract loss due to friction, add energy gained from magnetic attraction, then subtract all the components of impact loss, our sum would be zero (no energy created or destroyed through the process).

This is a perfect example of the principal.

Now measuring all of these would be very difficult. Your input could easily be measure, the friction loss could easily be measured, magnetic gain could be measured, and sound could be measured all in lab settings.

However, the heat would prove very difficult to measure as there would not be much and it would quickly dissapate. Deformation would also be difficult to measure, depending on the hardness of the material.

But if they could be measured, they would add up to a perfectly balanced system.

This is actually how we came to understand CoE. It was the early works of Rankine and Kelvin. It was through experimentation and measurements of initial energy vs final energy for any process that let us to believe energy can neither be created nor destroyed, only change form. To date, EVERY experiment and observation has confirmed this statement.

Like someone stated earlier, energy systems are rather simple once you understand what they actually do.

The best analogy I can think of is as follows:

Imagine a cup of water. This is your "total energy" for the system, each molecule representing a Joule (unit of energy).

Now, we can freeze the water, changing it's form. Just like a battery changes chemical energy to electric, or a motor changes electric to mechanical.

Now, even though the water has changed form, the number of molecules has remained the same. Similarly, an energy system can change the form of energy, but the number of joules remains constant.

We can always add water to the system, which is like adding gas to your car.

We can also take water from the system, which is like using a motor to do external work.

However, at no time are there suddenly molecules there (or not there) that we didn't input (or remove).

That last statement is the "watered down" version of the conservation of energy principal.

Hope that helps!

@ Bulls

What you are asking can be described by Kepler's work, but here's a simpler version:

As the satelite approaches earth from a distance x with velocity v, it builds speed. As it passes it's closest distance to earth, it is at it's maximum speed. As it pulls away from earth, it loses speed. Once the satelite is at a distance x, it is now traveling at velocity v again.

This is a perfect example of potential energy, converted to kinetic energy, back to potential energy.

Another good example is a pendilum.

At the top of the swing, it has no kinetic energy and maximum potential. As it swings down to the lowest point, it has maximum kinetic and no potential.

0 + m*g*h  = .5*m*v(^2) + 0

As it swings back up, all the kinetic energy is converted back to potential

.5*m*v(^2) + 0 = 0 + m*g*h

Simple and clean. And a perfect demonstration of CoE. To account for loss, add a "(frictional torque)*(radians of rotation)" to the left hand side. This is why it keeps getting lower and lower, as seen by the formulas. Go ahead, try em out!

(please notice that, assuming measurements are correct, your results will also be correct even though you never take into account the energy needed to build said pendulum! Exx..)

-PurePower

[purepower]

"Gravitational slingshot" is widely used concept in Space exploration, which enables our artificial satellites to accelerate on behalf of rotational and inertial momentum of the planet, which satellite is passing by...
So, energy is stolen from the kinetic energy of that planet.
Nobody worries, because it is the same as stealing a drop of water from all the oceans on Earth...
Cheers!

Oops, my mistake!

My example was referring to elliptical orbit, not the hyperbolic "slingshot" in question.

Spinner is correct.

-PurePower

[spinner]

@purepower

Lol, I was just about to start a post on hyperbolic/parabolic/elliptical paths stuff...
Thanks!