Electric potential energy is the energy of a charge based on A.
the magnitude of its charge and its position in an electric field.
B.
the magnitude of its charge, its mass, and its speed.
C.
its mass and height above a given reference point in an electric field.
D.
its speed and the direction of its motion relative to a second charge.

Amichelson interferometer operating at a 600 nm wavelength has a 3.02-cm-long glass cell in one arm. to begin, the air is pumped out of the cell and mirror m2 is adjusted to produce a bright spot at the center of the interference pattern. then a valve is opened and air is slowly admitted into the cell. the index of refraction of air at 1.00 atm pressure is 1.00028.how many bright-dark-bright fringe shifts are observed as the cell fills with air?