Please follow our discussion in besslerwheel.com/forum. Below is a copy of our last post there. (The copy is surrounded/limited up and down by double dashed lines.
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To ME.
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The link below describes how the experiment (and the related possible animation) has to take place. The link below contains four drawings, that is, these are Fig. 1A, Fig. 1B, Fig. 2A and Fig. 2B.
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https://mypicxbg.files.wordpress.com/2020/12/2020_fig1-2.pdf ---------------------------------------------
1) Firstly please look at Fig. 1A.
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1 - 1) The red block is called body 1.
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1 - 2) The green ramp and the blue cube are firmly attached one to another thus forming one united whole, which is called body 2.
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1 - 3) The center of mass of body 1 coincides with its geometric center.
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1 - 4) The center of mass of body 2 coincides with the geometric center of the blue cube.
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1 - 5) A spring of characteristic 4 (please look at our previous posts) is attached to the centers of mass of bodies 1 and 2, respectively.
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1 - 6) A straight (dashed) line "a" connects the center of mass of body 1 to the center of mass of body 2. The straight line "a" has the following 2 properties.
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1 - 6 -1) The straight line "a" is the longitudinal axis of symmetry of the spring.
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1 - 6 - 2) The straight line "a" is motionless, that is, it does not move sideways and/or does not rotate at any angle. Actually we illustrate here the point of view of an observer, who is motionless with respect to the straight line "a". In other words, this is the point of view of an observer, who is fixed to (with) the straight line "a".
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1 - 7) The experiment is carried out in a space station under weightlessness conditions. Friction is negligible.
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1 -
The sliding contact between the red block and the green ramp is never lost, that is, while sliding relative one to other the red block and the green ramp are always in contact.
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2) Let us now allow the spring to contract. (Please look at Fig. 1B.) The contraction of the spring generates 4 results, which take place simultaneously.
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2 - 1) Body 1 covers the distance "k".
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2 - 2) The centers of mass of bodies 1 and 2 approach each other while moving on the straight line "a".
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2 - 3) Body 1 rotates clockwise at some angle α. The related center of rotation is the center of mass of body 1.
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2 - 4) Body 2 rotates clockwise at some angle β. The related center of rotation is the center of mass of body 2.
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3) Please look at Figs. 2A and 2B. The experiment here is just the same with the only difference that now (a) the blue cube is bigger, (b) the related angles of rotation are smaller and (c) the distances, traveled by the two centers of mass (while moving on the straight line "a" and while approaching each other), are smaller too. In one word, the bigger the blue cube, the smaller the related angles of rotation and the smaller the distances, traveled by the two centers of mass (while moving on the straight line "a" and while approaching each other).
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Note 1. The sizes of the red block and the sizes of the green ramp do not change and remain constant. The same for distance "k", that is, k = const.
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Note 2. Figs. 1A and 2A illustrate the starting positions of the experiments and Figs. 1B and 2B illustrate the final positions of the experiments.
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4) What is the couple of forces, which causes the combined motion (straight-line motion + rotary motion) of bodies 1 and 2? These two forces (let us call them G and -G (or whatever capital Latin letter you choose)) are opposite in direction and equal in magnitude. The common line of action of these two forces is the straight line "a". Force G is applied to the center of mass of body 1 and is directed to the center of mass of body 2. Force -G is applied to the center of mass of body 2 and is directed to the center of mass of body 1. And the situation does not change and remains the same if the blue cube is bigger (or much bigger) than the green ramp and the red block.
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Shall we do the animation now in accordance with the four drawings and the related text above?
Everything seems to be clear now, doesn't it?
Looking forward to your answer.
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