<p>A particle is moving in one dimension (along x axis) under the action of a variable force. It&#39;s initial position was 16m&nbsp; right of origin. The variation of its position (x) with time (t)&nbsp; is given as x =&nbsp;<span class="equation">\(-3t^3+18t^2+16t\)</span>, where x is in m and t is in s.</p>

<p>The velocity of the particle when its acceleration becomes zero is _________m/s</p>