An object, moving with a speed of $6.25 \mathrm{~m} / \mathrm{s}$, is decelerated at a rate given by $\frac{d v}{d t}=-2.5 \sqrt{v}$ where $v$ is the instantaneous speed. The time taken by the object, to come to rest, would be:

Question:

An object, moving with a speed of $6.25 \mathrm{~m} / \mathrm{s}$, is decelerated at a rate given by

$\frac{d v}{d t}=-2.5 \sqrt{v}$ where $v$ is the instantaneous speed. The time taken by the object, to come to rest, would be:

  1. $2 \mathrm{~s}$

  2. $4 \mathrm{~s}$

  3. $8 \mathrm{~s}$

  4. (d) $1 \mathrm{~s}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics Motion in a Straight Line chapter.

JEE Main Previous Year 2011


Correct Option: 1

Solution:

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