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Captain's Log 21/12/12:

brianstrom999

GROUP: Members

POSTS: 84

Report this Sep. 01 2013, 10:31 am

 


Principle No 3:     All motion is Orbital:


As Kinetic Energy is added to an object and its velocity increases, so the radius of its "orbit" increases:


Here's a diagram for a cannon-ball - or it could be a Starship in a low-earth orbit.


Fuel or explosive is burnt, and the Chemical Energy gets converted into extra Kinetic Energy.


The radius, orientation and shape of the orbit will change: elliptical, circular, parabolic or hyperbolic.


 


 


 



 



As the object continues on its orbital journey, any extra Kinetic Energy is converted into extra Potential energy, and back again, as described in an earlier posting.  Here's the diagram of a standard orbital transition:


 


 



So let me get this right: Your Earth physics is based upon the idea that an electron has one unit of electrical charge, which is exactly equal and opposite to the charge on a proton, which is almost 2000 times bigger! Furthermore, these charges normally repel like charges, but not when electrons are close together in an atom, nor when protons are close together in an atomic nucleus! You must be crazy!

brianstrom999

GROUP: Members

POSTS: 84

Report this Sep. 01 2013, 10:43 am

 


If the object is a vehicle on the Earth's surface, it would need to get to 17,650 mph to reach orbital velocity (that's a lot of wind resistance).


Anything less, and the vehicle stays on the ground, though its pressure on the ground (you would say its "weight") will reduce as the velocity increases, becoming "weightless" at orbital velocity.


(love this pic from Harry Tonge.)


 


brianstrom999

GROUP: Members

POSTS: 84

Report this Sep. 02 2013, 4:23 am

 


If the object is a projectile, it will fall back to Earth if travelling at less than orbital velocity, and will give up its Kinetic Energy to the Earth.


 


brianstrom999

GROUP: Members

POSTS: 84

Report this Sep. 02 2013, 4:28 am

For these slower speed projectiles, the initial path of motion, before impact, is elliptical.


Of course, the object soon collides with the Earth and gives up its Kinetic Energy, but if you imagine the object could travel through the Earth, then its path would be an elliptical orbit with the centre of the Earth as one focus of the ellipse.


 


Principle No 3:     All motion is Orbital:


 


 


 


brianstrom999

GROUP: Members

POSTS: 84

Report this Sep. 03 2013, 11:57 am

 


Here's some typical parameters for Earth orbits:


 


Earth's surface: 4000 miles from Earth centre: Orbital speed 17,650 mph: Orbital time: 85 minutes.


Low Earth orbit: 4130 miles from Earth's centre: Orbital speed 17,450 mph: Orbital time: 89 minutes.


Geostationary: 22,236 miles from Earth's centre: Orbital speed 6,935 mph: Orbital time: 23hrs 56mins.


Average Moon Orbit: 244,000 miles from Earth's centre: Orbital speed 2,300 mph: Orbital time: 27.3 days.


 


 

brianstrom999

GROUP: Members

POSTS: 84

Report this Sep. 03 2013, 12:49 pm

 


Here's a general diagram to demonstrate the orbital motion around a Potential Energy Well.


 


Adding energy to the object will cause it to move to a higher orbit.


Removing energy will cause the object to move to a lower orbit.


 


Energy can be added or removed by burning fuel or by a collision with another object, depending on the direction of the fuel burn or collision.


 


Remember:


The total Energy of the objects and exhaust gases will remain constant -


The Principle of Conservation of Energy.


 


For an elliptical orbit, the object's Energy will be transposed between Kinetic Energy and Potential Energy, and back again, but its total orbital Energy will remain constant.