Motion in a Plane Physics NCERT Exemplar Solutions Class 12th Chapter Eleven Class 12th Physics

At time t = 0 a particle starts travelling from a height $7 \hat{z} c m$ in a plane keeping z coordinate constant. At any instant of time it's position along the $\hat{x} a n d \hat{y}$ directions are defined as 3t and 5t3 respectively. At t = 1s acceleration of the particle will be

Option 1 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mo>−</mo> <mn>3</mn> <mn>0</mn> <mover accent="true"> <mi>y</mi> <mo>^</mo> </mover> </mrow> </math> </span></p>

Option 2 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mn>3</mn> <mn>0</mn> <mover accent="true"> <mi>y</mi> <mo>^</mo> </mover> </mrow> </math> </span></p>

Option 3 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mn>3</mn> <mover accent="true"> <mi>x</mi> <mo>^</mo> </mover> <mo>+</mo> <mn>1</mn> <mn>5</mn> <mover accent="true"> <mi>y</mi> <mo>^</mo> </mover> </mrow> </math> </span></p>

Option 4 - <p><span class="mathml" contenteditable="false"> <math> <mrow> <mn>3</mn> <mover accent="true"> <mi>x</mi> <mo>^</mo> </mover> <mo>+</mo> <mn>1</mn> <mn>5</mn> <mover accent="true"> <mi>y</mi> <mo>^</mo> </mover> <mo>+</mo> <mn>7</mn> <mover accent="true"> <mi>z</mi> <mo>^</mo> </mover> </mrow> </math> </span></p>

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Vishal Baghel | Contributor-Level 10

6 months ago

Correct Option - 2

Detailed Solution:

x = 3t y = 5t³

$V_{x} = \frac{d x}{d t} = 3 V_{y} = \frac{d y}{d t} = 15 t^{2}$

$a_{x} = \frac{d V_{x}}{d t} = 0 a_{y} = \frac{d V_{y}}{d t} = 30 t$

$\vec{a} = 30 t \hat{j}$

at t = 1 sec, $\vec{a} = 30 \hat{j}$

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Physics NCERT Exemplar Solutions Class 12th Chapter Eleven 2025

Physics NCERT Exemplar Solutions Class 12th Chapter Eleven 2025

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