**Question:**

**The co-ordinates of a moving particle at any time ‘ $t$ ‘ are given by $x=\alpha t^{3}$ and $y=\beta t^{3}$. The speed of the particle at time ‘ $t$ ‘ is given by**

$3 t \sqrt{\alpha^{2}+\beta^{2}}$

$3 t^{2} \sqrt{\alpha^{2}+\beta^{2}}$

$t^{2} \sqrt{\alpha^{2}+\beta^{2}}$

$\sqrt{\alpha^{2}+\beta^{2}}$

Question of from chapter.

JEE Main Previous Year 2003

Correct Option: 2

**Solution:**

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