Which laser printer component applies a strong uniform negative charge to the drum?
1. >>Primary corona wire
2. Transfer roller
3. Fusing assembly
4. Piezoelectric nozzle
Explanation : The laser printer's primary corona wire (also called the charging roller) applies a strong negative charge to the photosensitive drum. This is the first step in preparing a page to be printed.
The fusing assembly uses heat and pressure to make the image on the paper permanent. This is the last step in the process.
The transfer roller (also called the transfer corona) applies a positive charge to the paper so that the negatively charged toner particles will be attracted to the positively charged areas on the paper. Because the laser reduced the negative charge in the areas to be printed, only those areas will have a positive charge after the transfer roller completes its task. Therefore, only those areas attract the toner.
A piezoelectric nozzle is used in an ink jet printer, not in a laser jet printer.
Objective: Printers and Scanners