Is the force of gravity affected by an object's mass?

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negitron said:
No, it would have a larger surface gravity. Hwever, at the same distance from the center of mass, both vehicles would have an identical pull.
This is an important point to remember the next time you are sucked into a black hole.
 
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What is the interest level in there being a questionnaire...
- that asks basic questions about a variety of disciplines (say, 10 questions per discipline for a smattering of disciplines)
- where the taker records the age, country of origin, field, and employment

Then we can see if any interesting patterns arise. For instance, it would seem obvious that a physicist will do better on the physics section than a biologist, but would the physicist do equally well across other disciplines, or what?

It could be interesting.
 
It is an interesting idea. The challenge would be in creating the questions, especially if one wished them to be of equivalent difficulty in each discipline.
 
Yeah, that's the trick. We'd almost need a team to come up with the questions, and if we all chip in, then who's left to take the test?
 
AUMathTutor said:
What is the interest level in there being a questionnaire...
- that asks basic questions about a variety of disciplines (say, 10 questions per discipline for a smattering of disciplines)
- where the taker records the age, country of origin, field, and employment

Then we can see if any interesting patterns arise. For instance, it would seem obvious that a physicist will do better on the physics section than a biologist, but would the physicist do equally well across other disciplines, or what?

It could be interesting.

Ophiolite said:
It is an interesting idea. The challenge would be in creating the questions, especially if one wished them to be of equivalent difficulty in each discipline.

Have different "masters" of each topic write the 10 questions for each section, and have them use "medium-range" questions. And most important, have them consult with each other on the questions they're using lol

I think that would be a fantastic idea.. I'd love to take that quiz
 
I'll get it started.
Math: 2 + 2 = ____ .
Physics: If you have two electrons and two neutrons, how many particles do you have altogether?
Chemistry: If you start with a molecule containing two atoms and you add another two atoms to it, how many atoms are in the new molecule?
Biology: If two horses have two foals, how many horses are there?
Astronomy: If there are two galaxies on the left of the photo image and two galaxies on the right, then how many galaxies are there all together?
Cosmology: Suppose there are two big bangs, and two big crunches. Then how many 'big' events are there?
Geography: If you visit two cities in the summer and two in the winter, then how many cities have you visited?
Philosophy: If two materialists are arguing with two idealists, how many philosophers are arguing?
Religion: If two angels can dance on the inner portion of the head of a pin and two can dance on the outer portion, then how many angels can dance on the head of a pin?

This should indicate who has a well rounded education.
 
Jimmy is retired, by the way. In case you couldn't tell.
 
This isn't physics, but I met a girl who thought the way unborn babies breathed was by breathing the "water" in the womb with their lungs. And apparently they inexplicably lose that ability once they're born.
 
jimmysnyder said:
I'll get it started.
Math: 2 + 2 = ____ .
How can I possibly answer this with only scalar values? 2i + 2j will give a distinctly different answer than (.5i+.866j+1.732k) + (1.5i+.886j+k)

Another math problem:

If a class has 20 boys and 20 girls, how many students are in the class?
If a class has 20 boys and girls, how many students are in the class?

This was actually a subject for discussion during a higher headquarters inspection of a squadron's evaluation scenarios. They initially claimed the regulation requirement for at least three ground system and satellite system malfunctions per scenario meant three of each.

To their credit, they eventually realized how stupid that sounded - they weren't very good at vector math. I explained how it took two of each to equal a total of three ... at which point I was kicked out and higher headquarters decided the squadron was doing things just fine.
 
BobG said:
This was actually a subject for discussion during a higher headquarters inspection of a squadron's evaluation scenarios. They initially claimed the regulation requirement for at least three ground system and satellite system malfunctions per scenario meant three of each.
Similair thing happened with 3G phone band license auction.
The auction rules said that bids had to be multiples of £1000, one bidder didn't have any competitors in their region but bid £2000 because the lawyers weren't convinced that £1000 was a multiple of £1000 !
 
D H said:


Note that the people inside the moonbase not equipped with those special heavy boots just float. The end scene shows that the heavy boot effect has limited applicability. Slap someone in the back and off he goes, only to get hit by a meteor streaking through the moon's thick atmosphere. Documented!


I couldn't help noticing, that when youtube users comment like this:

well, at least I'm not the only one who had a scientific issue with this commercial.. ooh, check out the bad continuity.. they're inside - floating - yet things like nametags and ties will hang like they're in normal Earth gravity.. yup.. I'm a geek.. lol

Why are people walking on the surface, but floating indoors? How does that work? There's gravity on the moon, but only outdoors?

they get voted thumb down as dumb comments, but when somebody responds like this:

the asteroid thing wouldn't work and fedex doesn't ship to the moon, i don't think theyre going for accuracy

it gets voted thumb up as good explanation why one shouldn't get stuck with little scientific inaccuracies.

It could be that the collection of people who voted in this isn't very large, but caught my attention anyway.
 
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DaveC426913 said:
Jimmy is retired, by the way. In case you couldn't tell.
Sadly no, I'm still working on my Master's thesis in Mathematics: The effect of a non-closed commutative arithmetic operator on a certain subset of the even integers. I already have a result. With proper care in choosing the subset, you can relax the condition that the operator be commutative.
 
Jimmy is single and has no social life by the way. In case you couldn't tell.
 
DaveC426913 said:
Jimmy is single and has no social life by the way. In case you couldn't tell.

Why are we talking about Jimmy? Is this some running gag that I'm not getting?
 
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ideasrule said:
Why are we talking about Jimmy? Is this some running gag that I'm not getting?
Jimmy's not threatened by ideasrule's question. Jimmy's happy for ideasrule.
 
ideasrule said:
Why are we talking about Jimmy? Is this some running gag that I'm not getting?
:biggrin:Jimmy spent a lot of time writing that post (#66) is all.
 
DaveC426913 said:
Jimmy is single and has no social life by the way. In case you couldn't tell.

Jimmy's wife told you that, didn't she.
 
D H said:


Note that the people inside the moonbase not equipped with those special heavy boots just float. The end scene shows that the heavy boot effect has limited applicability. Slap someone in the back and off he goes, only to get hit by a meteor streaking through the moon's thick atmosphere. Documented!


Easy Peasy. Thems magnetic boots.
 
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Chi Meson said:
I remember reading here on PF a couple of years ago, that sometimes 2+2=5, for large values of two.

Yes, Jimmy has laboured long and hard on errata page...
http://www.erratapage.com/
 
jimmysnyder said:
Math: 2 + 2 = ____ .

Answer: 1.
jimmysnyder said:
Cosmology: Suppose there are two big bangs, and two big crunches. Then how many 'big' events are there?

Answer: 2.
 
Oh God, can we not start this masturbatory science vs. religion thing again on these physics forums. Amen.
 
AUMathTutor said:
Oh God, can we not start this masturbatory science vs. religion thing again on these physics forums. Amen.

What does Moon hoaxing have to do with science versus religion? :confused:
 
JasonRox said:
The real idiots are those who believe the moon landing happened...

Haven't there been a few moon landings?