Question

Two conductors $A$ and $B$ are joined by a copper wire. If $A$ is positively charged and $B$ is uncharged, the direction of flow of electrons is

• A. $B$ to $A$
  
• B. $A$ to $B$
  
• C. no flow
• D. none of these.

Answer 1

The correct option is A $B$ to $A$

The current in the wire is due to the drifting of electrons inside a wire in a direction opposite to the flow of electrons. During their drifting they collide with their atoms vibrating about their mean position and lose some of kinetic energy to the vibrating atoms. The electrons are negatively charged particles and so, the electrons move towards the positively charged conductor A.
Hence, the direction of the flow of electrons in the copper wire is from B to A.