Neither ball has a charge.
Positive charge means that the particles have more protons than electrons.
Negative charge means that the particles have more electrons than protons.
Uncharged means that the particles have an equal number of protons to electrons.
In this example, the balls are hanging (heh) equally, they aren't repelling nor attracting each other. This means that both are uncharged, both balls have an equal number of protons and electrons.
Lets say that the left ball was positively charged (more protons) and the right ball was negatively charged (more electrons), the balls would attract (go closer to) each other.
Or lets say that both balls were either positively charged (both had more protons than neutrons), or even both were negatively charged (both had more neutrons than protons), the balls would repel (grow farther from) each other.
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(Just a friendly note, this is a physics question, not a biology question! You put it in the wrong category)
