Shalmanese
Platinum Member
Science cannot prove the non-existance of an invisible, pink unicorn.
Originally posted by: Mingon
Thats not technically falling to be pedantic 😛
and for their to be a forest you would still need and atmosphere to keep them alive.
Originally posted by: Pudgygiant
Nothing says it's a live tree. Just a tree. And all you squares are interpreting it to mean the 'plant' form of a tree. Why couldn't it be a family tree written on paper?
Sure it is! It's just falling from a great height. After all, Skylab fell back to Earth, didn't it?
Originally posted by: Mingon
Would a piece of paper fall or float 😀 and when it landed it would still make a noise
Sure it is! It's just falling from a great height. After all, Skylab fell back to Earth, didn't it?
Not really, it was caught up in the earths atmosphere then fell. The act of it falling only happened inside the atmosphere, outside it was in space and hence it was in orbit albeit a decaying one, so to technically fall it needs to be in an atmsophere being affescted by gravity 😛
Maybe that's how engineers think of falling. I never considered that it involved being in something that would slow down motion. Could we then say that nothing can float in space because there's no water or air?
Originally posted by: Mingon
Maybe that's how engineers think of falling. I never considered that it involved being in something that would slow down motion. Could we then say that nothing can float in space because there's no water or air?
Not quite sure I understand your point. To fall requires something to be affected by gravity does it not? whilst things are in space they cannot fall as their is no up/down do you not agree? As for floating in space that is a term which holds no true value, You are not floating as you are just not being affected by gravity. I would say being suspended in space is better than floating but pray tell what your explanation is?
Originally posted by: Mingon
the moon does have an atmosphere actually 😛 hence it requires an escape velocity
Originally posted by: Mingon
Whatever
Originally posted by: rjain
Originally posted by: Mingon
Whatever
The only thing you got wrong was the "hence".
To elaborate...
Escape velocity is reached when kinetic energy is equal to gravitational potential energy. That is,
1/2 m v^2 = G M m / r^2
v = sqrt(2 G M / r^2)
Nothing to do with atmosphere there
Originally posted by: Mingon
To elaborate...
Escape velocity is reached when kinetic energy is equal to gravitational potential energy. That is,
1/2 m v^2 = G M m / r^2
v = sqrt(2 G M / r^2)
Nothing to do with atmosphere there
Sorry but that is over simplifying the action of escaping the atmosphere.
Kinetic energy is required to accellerate the 'craft' yes/no
The craft is run on fuel which provides the kinetic energy yes/no
The fuel's energy is effected by the atmosphere yes/no
Any drag created due to an atmosphere will also effect the escape velocity yes/no
So to me at least the atmosphere of a planet does have an effect.
There's a reason Armstrong didn't fly away when he started walking on the moon.
Originally posted by: Mingon
There's a reason Armstrong didn't fly away when he started walking on the moon.
You mean apart from being weighed down.
Edit: Wow. I didn't even notice that you mentioned fuel in there. Almost like a mountain painted pink. That has no relationship to velocity. It's the propulsion system. In fact, escape velocity is defined in terms of projectile motion, i.e, without any propulsion. And a fuel's energy doesn't have to be affected by the atmosphere. Nothing that can escape the atmosphere can use such a fuel. That's why even the SR-71 can't escape the atmosphere. The engines just cut out. Rockets carry their own supply of oxidizers and satellites typically use nuclear energy.
Originally posted by: Mingon
Edit: Wow. I didn't even notice that you mentioned fuel in there. [...]
Yeah I know realised my error in that one just after posting 😱 but I figured the gase in the atmosphere would still have an effect on the burn pattern so I left it.
You're just thinking in terms of an engineer, not a scientist, that's all.
Escape velocity is a scientific term, really. It has nothing to do with how to build a vehicle to transport anything off a celestial body.
Originally posted by: Mingon
You're just thinking in terms of an engineer, not a scientist, that's all.
Escape velocity is a scientific term, really. It has nothing to do with how to build a vehicle to transport anything off a celestial body.
It still seems an over-simplification to me, but then its the little fine details that are important in my book, I crave accuracy in all things I hate the idea of adding 10% just to make sure - sloppy attitude.