Final answer:
The questions revolve around the concept of net electric charge in physics, including charge distribution in conductors and the resulting charge after objects come into contact. Key examples include charge neutralization within a conductor's cavity, charge equalization between touching conductive spheres, and charge identification through attraction and repulsion.
Step-by-step explanation:
The questions you've mentioned relate to the concept of net electric charge and its behavior on conductors and insulated objects in the context of physics. When addressing these questions, it's important to consider the laws of electrostatics, particularly the conservation of charge and the manner in which charges redistribute when conductors come into contact. Here are three instances demonstrating these principles:
- When a 2.0-μC charge is placed inside a cavity of a conductor with an excess charge of -5.0 μC, the surface of the cavity will acquire a charge of +2.0 μC to neutralize the enclosed charge, resulting in the outer surface having a net charge of -7.0 μC
- Two conductive spheres initially with +5.0q and -8.0q, upon contact and separation, will have an equal net charge of -1.5q each, assuming 'q' represents a unit of charge.
- An object that attracts neutral paper but repels a negatively charged balloon has a net positive charge, as it exhibits attraction due to polarization and repulsion due to like charges repelling.
Through these examples, one grasps the foundational behavior of electric charge in interactions involving conductors and charged objects.