Explain how electric current with Lorentz - Drude theory of electrons.

Hint: To get the correct answer you need to know that the electric current starts flowing when the flow of similar charges occurs in ordered motion.

Complete step-by-step answer:
Lorentz sought to establish a hypothesis in which the relative motion of the planet and the aether is (almost or completely) undetectable. He thus extended the contraction theory and concluded that not only the forces between electrons, but also the electrons themselves, had contracted in the line of motion.
Lorentz- Drude suggested that conductors such as metals contain a great number of free electrons.
The positive ions are fixed at their sites. (The Positive Ion Arrangement is called lattice).

In an open circuit, the negative ions (electrons) move at random in the lattice.

When the lattice is closed the electrons will be arranged in orderly movement. That's it. Is causing the flow of electric current.

Note: To make this concept clear, you need to know that 19th-century scientists Drude and Lorentz proposed that conductors such as metals contain a large number of free electrons while the positive ions are fixed at their locations. The Positive Ion Arrangement is called lattice. When the electrons are in ordered motion, a net charge crossing will occur through any cross section. This ordered motion of electrons is called electric current.