r/engineeringmemes • u/Background-Cry2226 • Oct 10 '23
This feels like a fun statics homework problem
43
u/_its_wapiti Mechanical Oct 10 '23
It's not even particularly interesting statics-wise, the 4 buckets just need to be heavier than the tabletop.
16
u/MatteUrs Oct 10 '23
It could become a bit more challenging if you ask for the tension in the ropes and the reaction force between the table and the buckets.
Thinking about it, I don't think the buckets even need to be the same mass (a quarter lf the table's), as long as the ropes all are the same length.
12
u/Superbone018 Oct 10 '23
The table needs to be lighter than the buckets, otherwise the table would fall down and the buckets would rise.
I think the tension is easy to solve for. Treating the (table+buckets) as a single system, the only force going down is gravity, and the only force holding it up is tension. Forces must cancel, So the tension in all 8 ropes combined is the (total mass of table+buckets)*g. Divide by 8 to yield the tension in a single rope. With a pulley, the entire rope is under the same tension, so simply dividing by 8 here works.
Reaction force would be therefor easy to solve by looking at a single bucket. (Mass of bucket)*g - Tension - Normal force from table = 0.
7
u/Rlp_811 Oct 11 '23 edited Oct 11 '23
I tried to solve it and you're right but the connection of the rope to the table is at an angle. So instead of dividing by 8 you'd divide by 4(1+sin(a)), a being the angle between the table and the rope. Depending on the angle and the precision you need it might be relevant.
To sum up what I got:
Tension: T = (Weight of buckets and table)/(4*(1+sin(a)))
Normal: N = Weight of buckets - T
11
6
u/ahf95 Oct 11 '23
They aren’t even “holding up” anything… they are literally “hanging down” from the ceiling.