Bar code readers use ________blank embedded in them to read bar codes.Multiple Choicecoprocessorsmagnetic cellsRFID microchipphotoelectric cells

Step 1: Break Down the Problem

We need to identify what technology is embedded in barcode readers that enables them to read bar codes.

Step 2: Relevant Concepts

Barcode readers typically use a method that can detect and interpret the patterns of bars and spaces that represent data.

Step 3: Analysis and Detail

• Coprocessors: Generally used to perform specific tasks alongside the main processor, not for reading bar codes.
• Magnetic cells: More commonly associated with magnetic storage or retrieval. Not applicable.
• RFID microchip: Used in RFID systems, which are different from traditional barcode scanning.
• Photoelectric cells: These cells can detect light and are commonly used in barcode readers to scan the contrast between the light and dark bars of the barcode.

Step 4: Verify and Summarize

The technology that enables barcode readers to detect and interpret the bar codes resides in the photoelectric cells. These cells are effective in distinguishing between the light reflected from the white spaces and the absence of light from the dark bars.

Final Answer

Barcode readers use photoelectric cells embedded in them to read bar codes.