3. Listening: A Simple DC Motor and Its Technical Principle

The simplest one from the huge family of electric motors seems to be a simple DC motor that often serves as a demonstration of a DC motor principle. Watch the video and complete this listening comprehension task.  

Now that you know some basic principle of a DC motor, it should not be so difficult to describe it. First, look at the diagram in your coursebook (Bonamy, D. (2011). Technical English Level 3 Coursebook. Pearson Longman, p. 65). Then complete the description of the motor technical principle here.