Physics · Motion in one Dimension

NEET (UG) 2025 — Question 14

In some appropriate units, time ( tt ) and position (x) relation of a moving particle is given by t=x2+xt=x^{2}+x. The acceleration of the particle is

  1. Option A:

    −2(x+2)3-\frac{2}{(x+2)^{3}}

  2. Option B:

    −2(2x+1)3-\frac{2}{(2 x+1)^{3}}

    Correct
  3. Option C:

    +2(x+1)3+\frac{2}{(x+1)^{3}}

  4. Option D:

    +22x+1+\frac{2}{2 x+1}

Answer: B

Step-by-step solution

t=x2+x\mathrm{t}=\mathrm{x}^{2}+\mathrm{x}

dtdx=ddx[x2+x]\frac{\mathrm{dt}}{\mathrm{dx}}=\frac{\mathrm{d}}{\mathrm{dx}}\left[\mathrm{x}^{2}+\mathrm{x}\right]

1v=2x+1\frac{1}{\mathrm{v}}=2 \mathrm{x}+1

v=(2x+1)−1…(i)\mathrm{v}=(2 \mathrm{x}+1)^{-1} …(i)

a=v dvdx=(2x+1)−1[−1(2x+1)−2×2]\mathrm{a}=\frac{v \mathrm{~d} v}{\mathrm{dx}}=(2 \mathrm{x}+1)^{-1}\left[-1(2 \mathrm{x}+1)^{-2} \times 2\right]

a=−1(2x+1)−3×2a=-1(2 x+1)^{-3} \times 2

a=−2(2x+1)−3a=-2(2 x+1)^{-3}

=−2(2x+1)3=-\frac{2}{(2 x+1)^{3}}

Answer key and solution verified before publishing.

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Exam
NEET (UG) 2025
Subject
Physics
Chapter
Motion in one Dimension
Topic
Uniformly Accelerated Motion
In some appropriate units, time ( t ) and position (x) relation of a… | NEET (UG) 2025 PYQ with Solution · DhiX AI