Plant leaves are green because they contain the green photosynthetic pigments, chlorophylls a and b. Popular science literature, and sometimes even textbooks, state that the greenness is caused by reflection of green light by chlorophyll. In the present study, we compared the reflectance spectra of green leaves to yellow or white leaves of the…

The laser pointer has been widely used to demonstrate some simple optics phenomena, like reflection, refraction, total reflection, and diffraction. However, the rays of laser light cannot be seen in the air because the scattered light is too weak. Many physics teachers use milk or smoke to visualize rays of laser light in physics labs, but it is…

Using polymerizable cholesteric liquid crystal (CLC) paints, we prepare circularly polarized freestanding films that enable students to acquire a basic understanding of circular polarization and molecular chirality. The polymerized helical structures of CLC films can exhibit brilliant structural colors by selective reflection of visible light…

The current pandemic era demands distance learning, including physics experiments on the topic of optics. One of the optical phenomena that needs to be explained in optic courses is fluorescence. This study offers a simple home experiment regarding the application of fluorescence, namely to identify the purity of olive oil using simple…

It's not surprising that rainbows have received a great deal of attention: in textbooks, in magazines, and on the web. They are, after all, beautiful, fascinating, occasionally awe-inspiring, even a little mysterious. They are an almost perfect blend of natural beauty and simple physics. Has everything that can be said about rainbows already been…

Previous studies have demonstrated that students have difficulties in applying the wave model of light to explain single-slit diffraction and double-slit interference patterns. In this study, we investigated if students could recognize typical interference and diffraction patterns at all. Eye movements of high-school students were measured while…

This paper demonstrates the use of a smartphone as a low-cost multi-channel optical fibre spectrophotometer suitable for physics laboratory classes. A custom-designed cradle and structure support were fabricated using 3D printing. The plastic optical fibres were arranged and inserted into the hole of the cradle to guide the light to the rear…

In the laboratory experiment described here, students synthesize silver nanostructures (AgNS) with different shapes and sizes to elucidate the shape- and size-dependent optical properties of nanostructured materials. Students also develop understanding of some thermodynamic and kinetic aspects of the synthesis process through this experiment. In…

Recognition of interference and diffraction patterns is a difficult task for both high-school and university students. Many students fail to observe important features of particular patterns and identify the differences among similar patterns. In this study, we investigated if performing students' investigative experiments can help high-school…

When doing experimental work of image formation by mirrors and (thin) lenses, it turns out again and again that students often have partially incorrect preconceptions about how the light emerging from an object passes through a lens and how the image is formed on a screen or directly in the eye. To check students' prior knowledge and help get a…

Semiconductor materials are at the core of electronics. Most electronic devices are made of semiconductors. The operation of these components is well described by quantum physics which is often a difficult concept for students to understand. One of the intrinsic parameters of semiconductors is their bandgap energy E[subscript g]. In the case of…

The quality of learning processes is mainly determined by the extent to which students' conceptions are addressed and thus conceptual change is triggered. Colour phenomena are a topic within initial instruction of optics which is challenging. A physically adequate concept of white light is crucial for being able to grasp the processes underlying…

This paper presents an experimental activity based on the absorption of light colours by pigments. The activity is constructed using a stepwise design and offers an opportunity for students and teachers to compare and generalize the interactions between light and pigment colours. The light colours composing an artificial rainbow produced in the…

Is moonlight "silver" or "cold"? In this paper we discuss the interesting combination of factors that contribute to the common descriptions of moonlight. Sunlight is reflected from the lunar surface and red-shifted. When traversing the atmosphere, moonlight is further depleted of short wavelength content by Rayleigh scattering.…

Surprisingly colourful views are possible from sparkling white snow. It is well known that similarly colourful features can exist in the sky whenever appropriate ice crystals are around. However, the transition of light reflection and refraction from ice crystals in the air to reflection and refraction from those in snow on the ground is not…