MCQ
A particle moves along $x$-axis as $x=4(t-2)+a(t-2)^2$. Which of the following statements is true?
- AThe initial velocity of particle is $4$
- ✓The acceleration of particle is $2\,a$
- CThe particle is at origin at $t=0$
- DNone of the above
✓
Answer
Correct option: B.
The acceleration of particle is $2\,a$
b
(b)
(b)
$x=4(t-2)+a(t-2)^2$
At $t=0, x=-8+4 a=4 a-8$
$v=\frac{d x}{d t}=4+2 a(t-2)$
At $t=0, \quad v=4-4 a=4(1-a)$
But acceleration, $\frac{d^2 x}{d t^2}=2 a$
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