Physics · 2019
JEE Main · 9 April 2019, Shift 2 · Q3
The position vector of a particle changes with time according to the relation r ( t )=15 t^2 i +(4-20 t^2) j. What is the magnitude of the…
The position vector of a particle changes with time according to the relation $\displaystyle \vec{r}(\mathrm{t})=15 \mathrm{t}^2 \hat{i}+\left(4-20 t^2\right) \hat{j}$. What is the magnitude of the acceleration at $\displaystyle \mathrm{t}=1$ ?
Official answer
(3)
$\displaystyle 50$
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JEE Main 2019 Physics question, with the answer from NTA’s final answer key. Where our answers come from.