Electric Potential and Electric Potential Energy - General Physics - Lecture Notes, Study notes of Physics

Download Electric Potential and Electric Potential Energy - General Physics - Lecture Notes and more Study notes Physics in PDF only on Docsity! Electric Potential and Electric Potential Energy Equipotential Surfaces W F s cos    (scalar quantity with SI units of Joules)  is the angle between the force and displacement vectors. Work done (W) on positive test charge=force on test charge (F) times parallel component of displacement (s) and s is in the direction of the vector field, E (all vectors!) Assume =0 (cos=1) Since FE q  , we can write ba s  W q E For conservative forces (such as gravitational and electric forces), we can define b abaW PE PE  Here, the change in electric potential energy is equal to the negative of the work done by the electric field: b a PE PE q E s     If the vector displacement of the positive charge is in the opposite direction of the electric field, E, (- s) the work done, baW , by the electric field is negative resulting in electric potential energy stored in charge-parallel plate system. a s F b  docsity.com Note: Applied force to move charge is equal and opposite to force created by electric field. Potential energy (PE) depends only on the initial and final placements of the test charge, but does not depend on path taken. Work and potential energy are scalar quantities. Electric Potential Difference=electric potential energy change per unit test charge (charge can be either positive or negative) b a ba ba b a PE PEV V V q q     W Electric Potential = potential energy per unit charge a a PE V q  SI units: Joule/Coulomb = Volt (V) Electric potential is a scalar quantity. For charged parallel plates (s=d): baV E d   So, ba VE d   Can now define E in units of either N/C or V/m Energy Conservation for charges in electric fields: docsity.com