GP Sound Waves

Which one of the following waves is used for detecting forgery in currency notes?

  1. Ultraviolet waves
  2. Infrared waves
  3. Radio waves
  4. Microwaves


Ultraviolet waves or UV rays are used for detecting fake and forged currency. The paper currency has a strip that is embedded in the note. This strip cannot be forged like that in the original currency.

So, to check for detecting forgery in currency notes, UV rays are used.

An authentic paper currency will fluoresce when it is illuminated by long wave ultraviolet light. The embedded stripe will fluoresce in accordance with the color chart.

The correct option is A.