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Physics · MOTION IN A STRAIGHT LINE
हिन्दीA particle moves along a straight line such that its position \( x \) at time \( t \) is given by \( x = t^3 - 6t^2 + 9t + 5 \). At what time(s) is the velocity of the particle zero?
Correct answer · Option C
\( t = 1\text{ s} \) and \( t = 3\text{ s} \)
Explanation
Velocity \( v = \frac{dx}{dt} = 3t^2 - 12t + 9 = 0 \Rightarrow t^2 - 4t + 3 = 0 \Rightarrow (t-1)(t-3) = 0 \), giving \( t = 1\text{ s} \) and \( t = 3\text{ s} \).
