I recently saw this done on a science programme but no explanation was given:
When you use the stem of a glass to act as a lens to view coloured writing, red writing is inverted and green writing is not - Why? please use as much detail as possible
Actually, there must be an inversion if the glass stem is acting as a lens. Please read the following, this is about an experiment:
An optics inversion tube can be used to conduct an inquiry activity that will help students understand how the lens works: Obtain pieces of glass rods, or fill up test tubes with water and cap or cover ...
Solution gives an example experiment on how a lens works and gives the proper explanation.