Comments by "nexus1g" (@nexus1g) on "Explained: Beaker Ball Balance Problem" video.

  1. C (edited from B, explained in reply). Since there's no string, it would be equal. But in this case, since he's holding the ping pong ball down, introducing additional force into the system on the ping pong ball's side, the buoyancy would push the ping pong ball up. However, since he's holding it down with greater force than buoyancy is forcing it up, Newton's Third law of motion applies which states that for every action there is an equal and opposite reaction. Therefore, the force of buoyancy being applied to the ping pong ball is also being applied to the scale, forcing the ping pong ball side down.
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  2. nexus1g However, I forgot about the force of the buoyancy being applied on the acrylic side as well. It would remain the same. My answer is changed to C. I predict that it will show the same weight now on both sides.
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