(a) Write the complete reaction equation for electron capture by 15 O . (b) Calculate

Lecture 7 Potential from a distribution of charges X V = 1 qi 4⇡✏0 ri §Smooth distribution 1 X qi 1 Z ⇢ V = = dV 4⇡✏0 i ri 4⇡✏ 0 r § of point charges is usually much simpler thanup calculating the electric field •It’s a scalar Electric Potential from Two Oppositely Charged Point Charges §The electric field lines from two oppositely charge point charges are a little more complicated §The electric field lines originate on the positive charge and terminate on the negative charge §The equipotential lines are always perpendicular to the electric field lines §The red lines represent positive electric potential §The blue lines represent negative electric potential §Close to each charge, the equipotential lines resemble those from a point charge 22 Electric Potential from Two Identical Point Charges §The electric field lines from two identical point charges are also complicated §The electric field lines originate on the positive charge and terminate at infinity § Again, the equipotential lines are always perpendicular to the electric field lines §There are only positive potentials §Close to each charge, the equipotential lines resemble those from a point charge 23 Example: Superposition of Electric