Final answer:
High-voltage wires are not insulated but are held by insulators; this statement is false. An inventor would indeed experience forces that could strip away clothes due to static, thus true. Electric-field lines of a positive charge radiate outward, also true. Inserting a dielectric in a capacitor reduces the electric field, so this statement is true. The energy of a rock alternates between kinetic and potential, making the final statement false.
Step-by-step explanation:
The main answer to the question about insulating materials on high-voltage wires is false. High-voltage wires are not typically wrapped in insulating materials because they are spaced far enough from objects and each other to prevent unwanted current flow; the surrounding air acts as an insulator. The insulating connectors are called insulators, which prevent the electricity from traveling to the towers. An eccentric inventor trying to levitate by charging himself and the ceiling would actually experience electrical forces that could cause his clothes to repel from his body if they had opposite charges, making this statement true. Static electricity can result in such unconventional outcomes, underscoring the potential for strong electric forces between charged objects. The statement about the electric-field lines from a positive charge is true. Electric field lines are used to represent the direction and relative strength of the electric field around charged objects. For a positive point charge, these lines radiate outward, indicating that the force exerted by the charge would be repulsive on other positive charges. Regarding the air-filled capacitor, inserting a dielectric between the plates reduces the electric field within the capacitor. This is because the dielectric material becomes polarized in the presence of the electric field, reducing the net field strength within the capacitor. Hence, the statement is truite energy of a rock thrown into the air changes forms between potential and kinetic energy during its motion. As the rock is thrown up, its kinetic energy is converted into potential energy, which reaches a maximum at the peak of its trajectory. As it falls, the potential energy is converted back into kinetic. So, the statement total is false because it incorrectly associates increases in height and velocity.