- 12
- 0
When I place an object in a table, how is the weight distributed in the four legs? Is there an mathematical calculations for that?
If you assume the table is rigid then you only need consider vertical forces and you can apply the principle of Moments in the simplest way. Whilst problems involving Moments are often only restricted to a two dimensional situation, it's easily applied to a three dimensional object like a loaded table.You could draw a vector diagram.
If you are really not sure about this, then you need to get hold of some material on statics. AS others have said, you need to learn about force vectors and moments.Thank you so much Fresh. Herewith I have attached word file just for you to visualize my question. In this case I would like to get a like to know from which point I need to draw the vector diagram. Thereby how do I get the individual vectors.
SET 1 | PRACTICAL VALUES | W | B | H | h | b | THEORETICAL VALUES (T) | |
R1 | 1.2 | 4.8 | 0.615 | 0.415 | 0.33 | 0.25 | R1T | 0.58348516 |
R2 | 1 | 4.8 | 0.615 | 0.415 | 0.33 | 0.25 | R2T | 0.39964737 |
R3 | 1.5 | 4.8 | 0.615 | 0.415 | 0.33 | 0.25 | R3T | 1.551572142 |
R4 | 0.8 | 4.8 | 0.615 | 0.415 | 0.33 | 0.25 | R4T | 2.265295328 |
TOTAL WEIGHT | 4.5 | 4.8 |
Clearly those figures don't match at all. What is the weight of the book and the weight of the table?
SET 1 PRACTICAL VALUES W B H h b THEORETICAL VALUES (T) R1 1.2 4.8 0.615 0.415 0.33 0.25R1T 0.58348516R2 1 4.8 0.615 0.415 0.33 0.25R2T 0.39964737R3 1.5 4.8 0.615 0.415 0.33 0.25R3T 1.551572142R4 0.8 4.8 0.615 0.415 0.33 0.25R4T 2.265295328TOTAL WEIGHT 4.5 4.8
'W' represents the actual weight of the object.
The Practical and the theoretical values of the reactive forces tabulated. The total seems to match somewhat but the individual values are not coinciding. That is my actual doubt. Think of it Ms Sophie. Do you think that I am proceeding in the correct method? If there is any other better choice kindly let me know. It is already 12.25 am. I am very tired thinking about it all day long. I need to sleep. I don't know what time it is now at your place. Tomorrow morning I will be eagerly waiting for your reply. Take care.
Those theoretical values don't look right to me, unless you have the book very near the edge. And then there may be a larger error due to the thickness of the table legs.Sorry the weight of the book is around 1 kg
S I'd also suggest you initially test the weight on a line down the centre of the table to check the 1D case. This will be a simpler way to test your measurements and calculations.
This will be a simpler way to test your measurements and calculations.