The position vector of a moving body at any instant of time is given as $\overrightarrow{r} = (5t^2 \hat{i} - 5t \hat{j}) \text{ m}$. The magnitude and direction of velocity at $t = 2 \text{ s}$ is,

  • A
    $5 \sqrt{15} \text{ m/s}$,making an angle of $\tan^{-1} 4$ with $-$ve $\text{Y}$ axis
  • B
    $5 \sqrt{15} \text{ m/s}$,making an angle of $\tan^{-1} 4$ with $+$ve $\text{X}$ axis
  • C
    $5 \sqrt{17} \text{ m/s}$,making an angle of $\tan^{-1} 4$ with $-$ve $\text{Y}$ axis
  • D
    $5 \sqrt{17} \text{ m/s}$,making an angle of $\tan^{-1} 4$ with $+$ve $\text{X}$ axis

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