Explain current formed in solid conductors in presence of external electric field.

Explanation

`rArr` Consider cylinder of radius R as shown in figure.

` rArr` We consider two thin circular disc which have + Q and - Q charge distributed over them.
`rArr` lf we attach two disc on two fiat surface of the cylinder current will be produced which is directed from positive to negative charge.
`rArr` Due to this electric field in cylinder electron will be accelerated due to this field toward + Q charge.
`rArr` These electron as long as they are moving will constitute electric current.
`rArr` In this condition current will be formed for very short time and will stop.
`rArr` Consider mechanism like cell or battery in which whatever amount of charge + Q be neutral similar charge of - Q is obtained at other end. In this situation by battery or cell current can be obtained continuously.