MCQ
$A$ particle is released from rest at origin. It moves under influence of potential field $U = x^2 - 3x$ , kinetic energy at $x = 2$ is ............... $\mathrm{J}$
- ✓$2$
- B$1$
- C$1.5$
- D$0 $
✓
Answer
Correct option: A.
$2$
a
$F=m a=-\frac{d U}{d x}$
$F=m a=-\frac{d U}{d x}$
$m v \frac{d v}{d x}=-2 x+3$
on integration
$m \frac{v^{2}}{2}=-x^{2}+3 x$
$K E=3 \times 2-2^{2}=2 J$
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