35 multiple-choice questions in College Board exam style. Each has four choices and a full explanation of why each option is right or wrong.
Watch for inverse-square traps. Doubling distance cuts force or field to one-fourth, not one-half: tripling distance cuts it to one-ninth.
Remember field is a vector, potential is a scalar. When multiple charges are involved, add potentials directly but add fields as vectors.
Use energy conservation to skip messy force calculations. If only the electric force acts, KE + U is constant: often faster than tracking force over a path.
Read the explanations even when you got it right. Each one teaches a small fact that often returns in a different form on the exam.