**Question:**

**The relation between time $t$ and distance $x$ is $t=a x^{2}+b x$ where $a$ and $b$ are constants. The acceleration is**

$2 b v^{3}$

$-2 a b v^{2}$

$2 a v^{2}$

$-2 a v^{3}$

Question of from chapter.

JEE Main Previous Year 2005

Correct Option: 4

**Solution:**

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