<p>You must apply Newton's law
$$ m\frac{\mathrm{d}\boldsymbol{v}}{\mathrm{d}t} = \boldsymbol{F}$$
which related the force $\boldsymbol{F}$ to the acceleration (=change of velocity). Note that positions, velocities, and forces are all <strong>vector</strong> quantities. Also note that as the objects move (change position), their mutual forces change (both direction and strength).</p>

<p>There is an enormous amound of literature on the resulting <strong>orbits</strong> for celestial bodies, going all the way back to Kepler and Newton. I suggest you look into elementary books or start with some Wikipedia articles.</p>

CC BY-SA 3.0
2014-12-07T10:07:34.000Z
2014-12-07T10:07:34.000Z
Walter
<p>I am doing some calculations, and I wanted to know that after using the gravity equation, $$F = G \frac{m_1m_2}{r^2}$$ if you can use $F$ and convert it into a speed, such as km/year, and also a direction or angle from the original direction. I am just looking into astronomy, and any help is appreciated.</p>

<orbit><gravity><solar-system>
How to convert a gravitational force to speed and direction
Pithon3
# How to convert a gravitational force to speed and direction

(Asked by: username_0 on 2014-12-07)

I am doing some calculations, and I wanted to know that after using the gravity equation, $$F = G \frac{m\_1m\_2}{r^2}$$ if you can use $F$ and convert it into a speed, such as km/year, and also a direction or angle from the original direction. I am just looking into astronomy, and any help is appreciated.

**Tags:** orbit, gravity, solar-system

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## 1 answers

### Answer by username_1 on 2014-12-07. Score: 1 | Accepted answer

You must apply Newton's law
$$ m\frac{\mathrm{d}\boldsymbol{v}}{\mathrm{d}t} = \boldsymbol{F}$$
which related the force $\boldsymbol{F}$ to the acceleration (=change of velocity). Note that positions, velocities, and forces are all **vector** quantities. Also note that as the objects move (change position), their mutual forces change (both direction and strength).

There is an enormous amound of literature on the resulting **orbits** for celestial bodies, going all the way back to Kepler and Newton. I suggest you look into elementary books or start with some Wikipedia articles.


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