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General
Easy
Question
A ball of mass m moving with constant velocity u collides with a smooth horizontal surface at O as shown. Neglect gravity and friction. The y-axis is drawn normal to the horizontal surface at the point of impact O and x-axis is horizontal as shown in the figure. About which point will the angular momentum of ball be conserved.
- point A
- point B
- point C
- None of these
The correct answer is: point B
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