JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
When the position vector \(\overrightarrow{ r }=x \hat{ i }+y \hat{ j }+z \hat{ k }\) changes sign as \(-\overrightarrow{ r }\), which one of the following vector will not flip under sign change ?
- A Linear momentum
- B Velocity
- C Acceleration
- D Angular momentum
Answer & Solution
Correct Answer
(D) Angular momentum
Step-by-step Solution
Detailed explanation
\(\vec{r}=x\hat{i}+y\hat{j}+z\hat{k}\) \(\vec{v}=\frac{d\vec{r}}{dt}=v_{x}\hat{i}+v_{y}\hat{j}+v_{z}\hat{k}\) \(\vec{p}=m\vec{v}\) \(\overline{L}=m(\vec{r}\times\vec{v})\) \(=(x\hat{i}+y\hat{j}+z\hat{k})\times m(v_{x}\hat{i}+v_{y}\hat{j}+v_{z}\hat{k})\) When sign of \(\vec{r}\)…
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