Skip to main content Breadcrumb Go home Go home Language English Deutsch Search Learning snippets Courses Lessons Videos Arguments Questions Exercises Formulary Illustrations Physics disciplinesElectrodynamicsMechanicsQuantum mechanicsSolid-state physicsOpticsThermodynamicsMathematics Log into an avatar Username Magic word Physics: Questions and AnswersDo you have a physics question that starts with What, How, Where or Why? Here you will find 5 questions and short but precise answers from different disciplines of physics.Questions of a specific discipline QuestionsPhysics QuestionsMechanics QuestionsThermodynamics QuestionsElectrodynamics QuestionsOptics QuestionsQuantum Mechanics QuestionsSolid State Physics QuestionsMathematics Max. Level - Any -Level 1 (suitable for all)Level 2 (suitable for students)Level 3 (for advanced students)Level 4 (for very advanced students) Question Why are field lines always perpendicular to conducting surfaces? Question Why are lattice vibrations called optical and acoustic? Question What is the difference between a series and parallel connection of resistors? Question What is the difference between orbital and angular velocity? Question Why can't electric field lines cross?