Jarrah White

[Allan F]

I have to ask a perhaps stupid question: The only Adam Savage I know about is partnered with a person resembling a whalrus. Is it him you refer to above?

[bknight]

I believe Luke referred to one of the myth busters.  I don't know if Jamie Hyneman is the walrus you are mentioning.

[Allan F]

Yes.

[Luke Pemberton]

I have to ask a perhaps stupid question: The only Adam Savage I know about is partnered with a person resembling a whalrus. Is it him you refer to above?

The Adam Savage I refer to is indeed the one from Mythbusters. Jarrah spent some time harrassing Adam and Phil Plait at TAM8, secretly recording them using a pen camera and spending his time stalking their every move. Jarrah came across as being an angry loner, and this was duly noted by both Adam and Phil, they dealt with him using some put downs. It was all rather amusing watching Jarrah take on a published PhD and a very smart and incisive TV celebrity. I would have been ashamed to post the footage if  had been slapped down in such a fashion. But no... 

[ka9q]

Yes. One of the requirements for being a hoax advocate is a complete lack of any sense of shame. That's in addition to a general cluelessness about physics, math, engineering, logic, human nature, etc.

[Gazpar]

The Adam Savage I refer to is indeed the one from Mythbusters. Jarrah spent some time harrassing Adam and Phil Plait at TAM8, secretly recording them using a pen camera and spending his time stalking their every move. Jarrah came across as being an angry loner, and this was duly noted by both Adam and Phil, they dealt with him using some put downs. It was all rather amusing watching Jarrah take on a published PhD and a very smart and incisive TV celebrity. I would have been ashamed to post the footage if  had been slapped down in such a fashion. But no... 

Its me or this guy Jarrah seems to have some ego issues?

[raven]

We generally do not make light of mental illness here. Some of us here do, in fact, grapple with such issues, and we're not JW. In my absolutely amateur opinion, I don't think anything Jarrah White does can really be categorized as such. Humans are quite capable of serious levels of self-delusion and ego without resorting to such an explanation.

[Gazpar]

We generally do not make light of mental illness here. Some of us here do, in fact, grapple with such issues, and we're not JW. In my absolutely amateur opinion, I don't think anything Jarrah White does can really be categorized as such. Humans are quite capable of serious levels of self-delusion and ego without resorting to such an explanation.

Sorry, I have changed it.

[smartcooky]

We generally do not make light of mental illness here. Some of us here do, in fact, grapple with such issues, and we're not JW. In my absolutely amateur opinion, I don't think anything Jarrah White does can really be categorized as such. Humans are quite capable of serious levels of self-delusion and ego without resorting to such an explanation.

I agree. You do not have to be suffering from any kind of mental health issues to be stupid.

[bknight]

Jarrah reminds me of a 5th grade classmate.  We were in the science part of the day, shortly after Sputnik 1, when my great teacher asked us "How can rockets put satellites into orbit?"(paraphrased because I can't remember the exact words almost 58 years ago).

Anyway I had watched everything I could concerning the satellite and raised my hand answering "it must overcome gravity".

My classmate raised his hand and said and said no it was inertial force that must be overcome.  The teacher put leashes on each of us and started a debate.  Sadly to say my limited amount of knowledge (science and debate skills)did not bring him up to speed. The teacher finally ended the debate in my favor, but he wasn't convinced with the idea.  Even later out of class he continued to argue the failed argument.  At least his excuse was being a 10 year old kid that hadn't been educated, yet.  I hope he changed his mind in the ensuing years.

[ka9q]

Actually, both gravity and inertia must be overcome. Gravity to get the spacecraft into space, and inertia to keep it there by moving it horizontally so fast that the earth falls away before the spacecraft can fall back onto it.

Ignoring thrust, air drag and other perturbations, the sum of a satellite's kinetic and potential (gravitational) energy remains constant. In a circular orbit they are also individually constant, but in an elliptical orbit some of the energy moves back and forth between the two forms.

In a low earth orbit nearly all of the total (~95%) is in kinetic energy.

KE + PE = constant is true even for an open, hyperbolic 'escape' trajectory like that of the Pioneers, Voyagers and New Horizons as they leave the solar system. As they gain potential energy climbing out of the sun's gravity well, they slow down to lose an equal amount of kinetic energy.

[bknight]

Of course, but to we 5th graders the question was what must be overcome.  MUCH later in studies inertia was studied, and inertia of an object must be increased to achieve orbit, I seem to remember the integral i_f =  i_o + .5 * m * v².  I guess one might infer an increase is an overcome.

[ka9q]

The inertia is just the mass; you don't change it to achieve orbit but you do have to overcome it in the sense that you have to exert a force on it for some period of time, and that force is proportional to the mass.

You also overcome gravity by exerting a force proportional to the mass.

You've probably noticed that rockets lift off vertically, then gradually arc over until they're horizontal. So at the beginning you're mostly overcoming gravity, and then you transition entirely into overcoming inertia.

[JayUtah]

The inertia is just the mass; you don't change it to achieve orbit...

Although the rocket does end up changing mass as fuel is expended.  Think of it as pushing a heavy shopping cart while your toddler throws your purchases overboard.  You're overcoming inertia all the time, but it gets easier the farther you go.  Inertia per se doesn't behave like that, but rocket inertia does.

[Dalhousie]

The inertia is just the mass; you don't change it to achieve orbit...

Although the rocket does end up changing mass as fuel is expended.  Think of it as pushing a heavy shopping cart while your toddler throws your purchases overboard.  You're overcoming inertia all the time, but it gets easier the farther you go.  Inertia per se doesn't behave like that, but rocket inertia does.

Uphill to make the analogy work.....

Personally I'd throw the toddler overboard and make him/her toddle