MCQ
The displacement is given by $x = 2{t^2} + t + 5$, the acceleration at $t = 2\;s$ is.........$m/{s^2}$
- ✓$4$
- B$8$
- C$10$
- D$15$
✓
Answer
Correct option: A.
$4$
a
(a) Displacement $x = 2{t^2} + t + 5$
(a) Displacement $x = 2{t^2} + t + 5$
Velocity $ = \frac{{dx}}{{dt}} = 4t + 1$
Acceleration $ = \frac{{{d^2}x}}{{d{t^2}}} = 4$ i.e. independent of time
Hence acceleration $ = 4\;m/{s^2}$
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