no. if acceleration due to buoyancy is greater than 20m/s2 force must be expended to drag those balls. force that could have been used to accelerate the rising balls.
Ok now that I know exactly what I need to refute this will be faster.
The weight of the ball is in the direction of motion, already by definition causing acceleration, regardless of values. However, I know you know this and are going to look for better explanation. Here goes:
The tension is in a closed loop. This means that something pulling at one point is pulling at all other points, including itself. It is tempting to think that if something is accelerating at a certain rate, anything accelerating more slowly would reduce the force of the system due to the lessened acceleration. However, due to being on a loop of string, any force it exerts to "drag" the other thing along will come back full circle and essentially be pulling on itself. Because of this, tensions in a closed loop are completely ignorable when determining the total force and acceleration of a system. Then, you have B-W on one side and W on other, and nothing else. Tensions involved will cancel themselves out due to the closed nature of the loop and the net force is B, which is greater than B-W. The falling ball will always help.
O I thought of something else too: You are right in saying that the acceleration of the system could be less, because the added mass could be greater than the force it provides by falling proportional to the force and acceleration of the other. But I think you are getting force and acceleration confused, because the system would always have more force and therefore output more energy (at least until a ball got to the valve), it just is also a possibility that the Force does not double while the mass does, reducing acceleration. The ball falling will still provide force to the system and do work in all cases.
This reminds me of a problem we did where we had two objects, one was pulled by a 15N force and the other was pulled by the weight of a mass weighing 15N, and we needed to decide if the acceleration of the object being pulled would be greater in one or identical. The first one would actually have more acceleration, even though it is being acted upon by the same force. The mass of the second object is what changes it.
How about "it just won't work and it's clearly obvious?"
You guys have blown this way out of proportion lol.
To me I am explaining a physics concept like I do almost every day to my lab partner who would probably be getting an D or an F if I didn't help. I don't exactly see it as blowing it out of proportion or a fight.