MCQ
In the figure shown, a particle is released from the position $A$ on a smooth track. When the particle reaches at $B$, then normal reaction on it by the track is .........
- A$2 m g$
- ✓$m g$
- C$\frac{2}{3} m g$
- D$\frac{m^2 g}{h}$
✓
Answer
Correct option: B.
$m g$
b
(b)
(b)
Using Mechanical energy conservation
$m g(3 h)=m g(2 h)+\frac{1}{2} m u^2$
$m g h=\frac{1}{2} m v^2$
$v^2=2 g h$
$m g+N=\frac{m v^2}{h}=\frac{m(2 g h)}{h}$
$N=m g$
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