A) \[36\hat{k}\]
B) \[-34(\hat{k}-\hat{i})\]
C) \[48(\hat{i}+\hat{j})\]
D) \[-48\hat{k}\]
Correct Answer: D
Solution :
\[\vec{L}=m[\vec{r}\times \vec{v}]\] \[m=2kg\] \[\vec{r}=2t\,\hat{i}-3{{t}^{2}}\hat{j}\] \[=4\,\hat{i}-12\hat{j}\,(At\,t=2\,sec)\] \[\text{\vec{v}=}\frac{d\vec{r}}{dt}=2\hat{i}-6t\,\hat{j}=2\hat{i}-12\hat{j}\] \[\text{\vec{r}}\times \text{\vec{v}}\,\text{=(4}\hat{i}-12\,\hat{j})\times (2\hat{i}-12\hat{j})\] \[=-24\hat{k}\] \[\vec{L}=m(\vec{r}\times \vec{v})\] \[=-48\hat{k}\]You need to login to perform this action.
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