When the position vector vec{r} = xhat{i} + y | vedclass

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(D) The position vector is given by $\vec{r} = x\hat{i} + y\hat{j} + z\hat{k}$.When $\vec{r} \rightarrow -\vec{r}$, the velocity vector $\vec{v} = \fr

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Angular momentum

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(D) The position vector is given by $\vec{r} = x\hat{i} + y\hat{j} + z\hat{k}$.When $\vec{r} ightarrow -\vec{r}$, the velocity vector $\vec{v} = \frac{d\vec{r}}{dt}$ also changes sign to $-\vec{v}$.Linear momentum $\vec{p} = m\vec{v}$ changes sign to $-m\vec{v} = -\vec{p}$.Acceleration $\vec{a} = \frac{d\vec{v}}{dt}$ changes sign to $-\vec{a}$.Angular momentum is defined as $\vec{L} = \vec{r} 	imes \vec{p} = \vec{r} 	imes (m\vec{v})$.When $\vec{r} ightarrow -\vec{r}$ and $\vec{v} ightarrow -\vec{v}$, the new angular momentum $\vec{L}' = (-\vec{r}) 	imes (-m\vec{v}) = (-1)(-1)(\vec{r} 	imes m\vec{v}) = \vec{L}$.Thus, the angular momentum does not flip its sign.

When the position vector $\vec{r} = x\hat{i} + y\hat{j} + z\hat{k}$ changes sign to $-\vec{r}$, which one of the following vectors will not flip its sign?

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