The position \(x\) of a particle varies with time \((t)\) as \(x=a t^{2}-b t^{3} .\) The acceleration at…
- \(\frac{2 a}{3 b}\)
- \(\frac{a}{b}\)
- \(\frac{a}{3 b}\)
- zero
Solution
x=a t^{2}-b t^{3} \\
\text {velocity }=\frac{d x}{d t}=2 a t-3 b t^{2} \\
\text { and acceleration }=\frac{d}{d t}\left(\frac{d^{2} x}{d t^{2}}\right)=2 a-6 b t
\end{array}\)
Acceleration will be zero if
\(2 a-6 b t=0 \Rightarrow t=\frac{2 a}{6 b}=\frac{a}{3 b}\)
Asked in: JEE Mains - Motion In One Dimension - Chapter Test