How do black (UV) lights work? How do black (ultraviolet) lights work? A black light looks dark purple, but most of the light it emits is in the ultraviolet (UV) range of the spectrum, which is invisible to the human eye. Under a UV light, white clothes, our UV poster [link], glow in the dark and many fluorescent coloured items emit a bright glow. What they all have in common is that they contain phosphors. A phosphor is any substance that absorbs energy and re-emits it as visible light. Under a black light, phosphors convert the UV radiation they receive into visible light.
Granola is a breakfast food and snack food consisting of rolled oats, nuts, honey, and sometimes puffed rice, that is usually baked until crisp. During the baking process the mixture is stirred to maintain a loose, breakfast cereal-type consistency. Dried fruits, such as raisins and dates, are sometimes added.
A flapjack, muesli bar, cereal bar, or granola bar is a sweet tray-baked oat bar made from rolled oats, butter, brown sugar and golden syrup.n other countries, including Canada, the United States, and South Africa, such products are referred to as  granola bars . In the UK, the term cereal bar is often used to describe products which contain fruits, nuts, other cereals apart from oats, and, occasionally, chocolate.