Question
State Newton's law of gravitation in vector form.
✓
Answer
The force of attraction between a pair of masses m1 and m2 separated by a length 'r' is given by.
$\overrightarrow{\text{F}_{12}}=-\frac{\text{Gm}_1\text{m}_2}{\text{r}_2}\hat{\text{r}}_{21}$
$[\text{F}_{12}\rightarrow\text{force on }1\text{ due to }2].$
$\hat{\text{r}}\rightarrow\text{Points from }2\text{ to }1.$
-ve sign shows that the force is attractive.
$\overrightarrow{\text{F}_{12}}=-\frac{\text{Gm}_1\text{m}_2}{\text{r}_2}\hat{\text{r}}_{21}$
$[\text{F}_{12}\rightarrow\text{force on }1\text{ due to }2].$
$\hat{\text{r}}\rightarrow\text{Points from }2\text{ to }1.$
-ve sign shows that the force is attractive.
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