What is the process of separating positive and negative charge in an object's atoms due to an external electric field?

• A. Polarization
• B. Electric field
• C. Static charge
• D. Ohm

Answer: (A)

When an external electric field is applied, the charges inside atoms or molecules shift relative to their nuclei, creating tiny dipoles. This is polarization—the separation of positive and negative charges within each particle, so the object becomes polarized while keeping overall neutrality. In insulating materials, bound electrons are displaced opposite to the field while nuclei shift with it, producing a net dipole moment without free charges moving freely through the material. This internal separation weakens the field inside the material by aligning the dipoles with the field. It’s not about the field itself, a net static charge appearing on the object, or a relationship between voltage and current; rather, it’s about the induced dipole moment from charge separation within the atoms or molecules.