A particle is moving in one dimension (along $x$ axis) under the action of a variable force. It's initial position was $16 \mathrm{~m}$ right of origin. The variation of its position $(x)$ with time $(t)$ is given as $x=-3 t^3+18 t^2+16 t$, where $x$ is in $\mathrm{m}$ and $\mathrm{t}$ is in $\mathrm{s}$.
The velocity of the particle when its acceleration becomes zero is _________ $\mathrm{m} / \mathrm{s}$.
Answer (integer)
52
Solution
<ul>
<li><strong>Position (x):</strong> The particle's location on the x-axis at a given time.</li><br>
<li><strong>Velocity (v):</strong> The rate of change of position with respect to time</li>
</ul>
<p>( $v = \frac{dx}{dt}$ ).</p>
<ul>
<li><strong>Acceleration (a):</strong> The rate of change of velocity with respect to time</li>
</ul>
<p>( $a = \frac{dv}{dt}$ ).</p>
<p>The particle's position is given by:</p>
<p>$x(t) = -3t^3 + 18t^2 + 16t$</p>
<p>We need to find the velocity when the acceleration is zero.</p>
<ol>
<li><strong>Find the Velocity (v) and Acceleration (a) Functions:</strong></li>
</ol>
<ul>
<br/><li>Velocity:</li>
</ul>
<p>$v(t) = \frac{dx}{dt} = -9t^2 + 36t + 16$</p>
<ul>
<li>Acceleration:</li>
</ul>
<p>$a(t) = \frac{dv}{dt} = -18t + 36$</p>
<ol>
<li><strong>Find the Time (t) When Acceleration is Zero:</strong></li>
</ol>
<p>$a(t) = 0$</p>
<p>$-18t + 36 = 0$</p>
<p>$t = 2 \text{ seconds}$</p>
<ol>
<li><strong>Calculate the Velocity at t = 2 seconds:</strong></li>
</ol>
<p>$v(2) = -9(2)^2 + 36(2) + 16$</p>
<p>$v(2) = 52 \text{ m/s}$</p>
<strong>Answer:</strong>
<p>The velocity of the particle when its acceleration becomes zero is 52 m/s.</p>
<p></p>
About this question
Subject: Physics · Chapter: Kinematics · Topic: Motion in a Straight Line
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