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Gravitation — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsGravitation2 Marks
Question
A planet moving along an elliptical orbit is closest to the Sun at a distance $r_1$ and farthest away at a distance of $r_2$. If $v_1$ and $v_2$ are the linear velocities at these points respectively, then find the ratio $\frac{\text{v}_1}{\text{v}_2}.$
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Answer

From the law of conservation of angular momentum, $\text{mr}_1\text{v}=\text{mr}_2\text{v}_2$ $\Rightarrow\text{r}_1\text{v}_1=\text{r}_2\text{v}_2$ $\frac{\text{v}_1}{\text{v}_2}=\frac{\text{r}_2}{\text{r}_2}$

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