- #1
AlchemistK
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Ok, just a few minutes back, a tic-tac slipped from my hand and fell to the ground.
The second bounce was to a lower height than the first (which is expected because e*<1) but then as it took the third bounce, it rose to a height higher than the one reached by it than in the second bounce.
I had observed this phenomenon before in pebbles, but today I sat down and started thinking about it, I came up with the following result :
I noticed (after dropping the tic-tac about a hundred times) that the height of a bounce is higher than the one preceding it only in one particular case : when the tic-tac hits one end on the floor first and then hits the floor a second time before bouncing back.
To make sense of this, I followed energy conservation.
The tic-tac originally has a potential energy of mgh and when it bounces back to a new height, it has no transnational kinetic energy, some potential energy and most importantly: Rotational kinetic energy.
Now to make the tic-tac reach a max height, the rotational kinetic energy would have to be minimum.
So what actually happens is that when a tic-tac hits the floor a second time in the same cycle, it gets a torque in the opposite direction to what it got in the first hit in the same cycle, hence reducing the rotational and by conservation of energy, making it reach to a higher height.
That's what I came up with, is it even remotely correct to what is actually going on? Any other thoughts?*e = coefficient of restitution
The second bounce was to a lower height than the first (which is expected because e*<1) but then as it took the third bounce, it rose to a height higher than the one reached by it than in the second bounce.
I had observed this phenomenon before in pebbles, but today I sat down and started thinking about it, I came up with the following result :
I noticed (after dropping the tic-tac about a hundred times) that the height of a bounce is higher than the one preceding it only in one particular case : when the tic-tac hits one end on the floor first and then hits the floor a second time before bouncing back.
To make sense of this, I followed energy conservation.
The tic-tac originally has a potential energy of mgh and when it bounces back to a new height, it has no transnational kinetic energy, some potential energy and most importantly: Rotational kinetic energy.
Now to make the tic-tac reach a max height, the rotational kinetic energy would have to be minimum.
So what actually happens is that when a tic-tac hits the floor a second time in the same cycle, it gets a torque in the opposite direction to what it got in the first hit in the same cycle, hence reducing the rotational and by conservation of energy, making it reach to a higher height.
That's what I came up with, is it even remotely correct to what is actually going on? Any other thoughts?*e = coefficient of restitution