Gravitational Path of an Object

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The discussion focuses on determining the path of an object entering gravitational pull from a specified point with a given velocity, while neglecting air resistance. The initial equations provided for the object's trajectory include components for x, y, and z coordinates, incorporating gravitational acceleration terms. A participant critiques the application of these equations, suggesting a lack of understanding of the underlying theory and recommending foundational texts for proper study. The recommended books emphasize the importance of grasping astrodynamics principles to avoid future errors in calculations. Understanding the theoretical framework is essential for accurate application of gravitational equations.
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What is the path of an object entering the graviational pull starting at a point [x_{0}, y_{0}, z_{0}] with a velocity [V_{0x}, V_{0y}, V_{0z}] neglecting air resistance? This is what I have thus far:

x(t)=x_{0}+V_{0x}*t-g_{x}*t^{2}
y(t)=y_{0}+V_{0y}*t-g_{y}*t^{2}
z(t)=z_{0}+V_{0z}*t-g_{z}*t^{2}

where
g_{x}=\frac{G*M}{r_{x}}
g_{y}=\frac{G*M}{r_{y}}
g_{z}=\frac{G*M}{r_{z}}

and the axis projected on the r-axis
r_{x}=x*cos\theta*sin\phi
r_{y}=y*sin\theta*sin\phi
r_{z}=z*cos\phi

After introducing \theta and \phi the whole thing becomes difficult. Is there an easier way?
 
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Philosophaie said:
What is the path of an object entering the graviational pull starting at a point [x_{0}, y_{0}, z_{0}] with a velocity [V_{0x}, V_{0y}, V_{0z}] neglecting air resistance? This is what I have thus far:

x(t)=x_{0}+V_{0x}*t-g_{x}*t^{2}
y(t)=y_{0}+V_{0y}*t-g_{y}*t^{2}
z(t)=z_{0}+V_{0z}*t-g_{z}*t^{2}

where
g_{x}=\frac{G*M}{r_{x}}
g_{y}=\frac{G*M}{r_{y}}
g_{z}=\frac{G*M}{r_{z}}

NO!

Philosophaie, based on your other posts, you have a marked tendency to apply equations randomly and incorrectly. Correcting these equations would be a disservice to you because you not understand the theory. Without this understanding, you might use the right equation this time, but you will use the wrong equations again in the future. Please, read a book. Here are three:

Bate, Mueller, White, "Fundamentals of Astrodynamics". [URL]https://www.amazon.com/dp/0486600610/?tag=pfamazon01-20[/URL][/URL]
Cost at Amazon: $16.61

Vallado, "Fundamentals of Astrodynamics and Applications". [URL]https://www.amazon.com/dp/1881883140/?tag=pfamazon01-20[/URL]
Cost at Amazon: $63.95.

Roy, "Orbital Motion". [URL]https://www.amazon.com/dp/0852742290/?tag=pfamazon01-20[/URL]
Cost at Amazon: $70.00.

Cost of these at a library: Free.
 
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Topic about reference frames, center of rotation, postion of origin etc Comoving ref. frame is frame that is attached to moving object, does that mean, in that frame translation and rotation of object is zero, because origin and axes(x,y,z) are fixed to object? Is it same if you place origin of frame at object center of mass or at object tail? What type of comoving frame exist? What is lab frame? If we talk about center of rotation do we always need to specified from what frame we observe?

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