A Van De Graaff generator cannot create sparks inside its dome if a wire connects the outside and inside surfaces, as both will be at the same electric potential. The dome maintains a higher potential than the charging belt, but without a ground connection, the inside remains neutral and lacks an electric field. To charge a capacitor inside the dome, a ground connection must be established, which can be done by running a cable outside the dome. The discussion clarifies that while the inside appears neutral, it can have potential if connected to ground. Understanding these principles is crucial for effectively utilizing Van De Graaff generators in experiments.
