Space Science Quiz

[AAJIII]

Ten questions about space, I got 9 out of ten.

The answers and explainations are at the bottom of the page.



http://www.space.com/scienceastronom...on_041123.html

[Russianwolf]

missed the Gravity question. What they discribe as "Deep Space" is not what I define it as.

[rosesunkist]

Gravity is funny. It is everywhere, the weakest of all natural forces, but it is the most noticeable. No matter the distance or the masses, two objects exert some gravitational force on each other. Like if you jump, the Earth moves a bit, but since the Earth's mass is way greater than your own, it does not move nearly as much as you do. It is actually kinda fun to play around with if you're into that kind of science talk.

F(gravity) = (G* mass1 * mass2) / distance^2

where G= 6*10^-11

[meika123]

F(gravity) = (G* mass1 * mass2) / distance^2

where G= 6*10^-11

Huh???

Dave in NC

[Anna]

Gravity is funny. It is everywhere, the weakest of all natural forces, but it is the most noticeable. No matter the distance or the masses, two objects exert some gravitational force on each other. Like if you jump, the Earth moves a bit, but since the Earth's mass is way greater than your own, it does not move nearly as much as you do.

I think the principle involved there is the conservation of momentum, not gravity. Gravity is also not the "most noticeable" per se. It is only noticeable when you have great masses involved, i.e. planets. Otherwise, it's generally negligible.

And you missed the units involved in your value of G. In physics, a quantity is pretty much meaningless unless the units are defined. And we all know that the universal gravitational constant is not dimensionless, right?

[gsmittle]

I think the principle involved there is the conservation of momentum, not gravity. Gravity is also not the "most noticeable" per se. It is only noticeable when you have great masses involved, i.e. planets. Otherwise, it's generally negligible.

And you missed the units involved in your value of G. In physics, a quantity is pretty much meaningless unless the units are defined. And we all know that the universal gravitational constant is not dimensionless, right?

Ummmm....sure. But I got 10 of 10. I'm such a geek!

g.

[rosesunkist]

Ah...Who needs units? Foot, hour, gallon...it's all the same!!!

For those of you out there that really want to know the units(I'm sure there are lots of y'all) lol....

G= 6.6742* 10^-11 N m^2 / kg^2

Now you can all sleep easier without that constant nagging feeling. The dropped units were an old habit, kinda hard to kick them you know....

What I meant with "most noticeable" is that of the four fundamental forces found in nature is that it is the one we are most cognizant of, we most easily identify, because of the distance at which it works(all distances) and that it affects all objects with mass(no matter the difference in mass). If I remember right, the electromagnetic force is the strongest. And it is what causes you to be able to actually touch things. If not for this force, your hand would simply pass through what you try to grab, being that atoms are pretty much empty space(at any one moment). I'm no expert, but I like to try and keep up on things, you know?

[Jaden]

I guess I'm a geek too...........10 for 10

[Russianwolf]

I never took physics, but I think we can agree that the gravity exerted on an object in Deep Space (ie, in areas far outside of galaxies) would be negligable to the point of being unmeasurable. And for all intensive purposes be non-existent.

also there are theories of dimensions with no mass at all. without mass, there can be no gravity.

[430752]

8 of 10 but Objection!

I missed the second (life can exist in space) and fourth (we've found some sort of life beyond earth). Anyway, I demand a recount since the explanation for the answer to #2 renders their answer to #4 incorrect. We put life on the moon, it existed outside of earth (last I checked, while the moon may orbit earth, it is not earth, not part of our ecosystem or within our atmosphere, etc.). Thus, I should have a more respectible 9 of 10!

so there.

curt j.

[scorrpio]

According to 'big bang' theory, gravity will eventually collapse our Universe into a point mass. It is everywhere. Now matter how deep into space you get, any object will gravitate toward whatever body has the largest mass/distance^2 coefficient.
On Earth, gravity other than that of Earth is most visible in the form of tides: gravitational pull of the Moon causes water to rise.

I got 9 out of 10, cause I was sure I once read that there were some traces of viral life discovered on Venus....

[gjbivin]

For those of you out there that really want to know the units(I'm sure there are lots of y'all) lol....

G= 6.6742* 10^-11 N m^2 / kg^2

Now you can all sleep easier without that constant nagging feeling.

Do I groan now, or would it be easier after I sleep?

[Tom Miller]

...I got 9 out of 10, cause I was sure I once read that there were some traces of viral life discovered on Venus....

Maybe you're thinking of Ur...no, must...resist...sophomoric...potty...humor....



Regards,
Tom
I think I just discovered another strong, almost irresistable force.

[Wood_workur]

10 out of 10. I must be pretty up to date on knoledge

[RmeDad]

GRAVITY SUCKS!