Input devices

Question 1

Scanning a barcode

Answer 1

Shines a laser onto the barcode and the barcode reflects the white spaces back. Photoelectric cells detect the reflected light and convert it to digital data which can be read by a computer.

Question 2

How does a mouse work?

Answer 2

A red LED light is reflected off a surface and any movements are detected be a sensor made up of an array of photo-sensitive diodes

Question 3

What is an input device?

Answer 3

Transfer of data from outside a computer to its main memory.