Question

The current is zero in a conductor when no potential difference is applied because: 

A. the electrons are not moving 

B. the electrons are not moving fast enough 

C. for every electron with a given velocity there is another with a velocity of equal magnitude and opposite direction. 

D. equal numbers of electrons and protons are moving together 

E. otherwise Ohm’s law would not be valid

Answer 1

C. for every electron with a given velocity there is another with a velocity of equal magnitude and opposite direction.