In this paper, a very simple and low-cost setup design is described for the Seebeck coefficient measurement of the disc and rod-shaped specimens. The setup has been tested for its reliable working by measuring the Seebeck coefficients of standard samples; measured values match with the literature. The setup can be built with commonly available raw…

As intriguing optical phenomena that occur in nature, mirages are widely known and often mentioned in physics classes when introducing the basics of optics. In the atmosphere, a mirage occurs under the condition of vertical variations in air density, which are usually caused by a temperature gradient. The light rays are continuously refracted and…

Experimental results are presented concerning a bead sliding on a rotating, horizontal rod. If the rod rotates at constant angular velocity then the sliding speed in the radial direction increases exponentially with time, provided that the rotation speed is sufficient to overcome friction. Otherwise the bead rotates in a circular path of constant…

An electric motor converts electrical energy into mechanical work and an electric generator converts mechanical work into electrical energy. The symmetry between the motor and generator naturally leads to questions about creating a perpetual motion machine. The allure of this question has inspired textbook problems, physics education articles, and…

A simple experimental setup using a smartphone and a pair of speakers is presented to perform an accurate experiment on interference of two point sources. The proposed experiment allows simple but interesting measurements to be done to introduce students to interference and diffraction phenomena. As such, the experiment effectively introduces the…

Under most conditions, a liquid mixture does not have long-range structural order and may be considered to be a homogeneous collection of molecules in random motion. However, if a single-phase critical mixture of a partially miscible liquid--liquid system is subjected to a small temperature jump into the two-phase region, then structural coherence…

Water electrolysis is used to teach important and fundamental concepts in chemistry. In practical water electrolysis experiments, it is difficult to achieve the ideal 2:1 ratio of hydrogen to oxygen. This work demonstrates an experimental setup comprising multiple water electrolysis cells connected in series to simultaneously visualize the effects…

As simple and ubiquitous redox-active organic molecules, quinones participate in diverse electron transfer processes in chemistry and biological systems for energy transformation and signal transduction. We introduce here a practical exercise to study the redox potentials of benzoquinone and its two derivatives by combining the electrochemistry…

Already when they enter primary school, children have rich everyday experience with factors influencing the rate of liquids' evaporation. Tea spilled into a large puddle on the table evaporates more rapidly than the same amount remaining in the cup, laundry hanging on a clothesline dries faster on a hot and windy day in comparison with a cold and…

A hula hoop rotating around a person's waist is an example of circular motion where the centripetal force on the hoop is directed towards the centre of the circle rather than the centre of the hoop. The friction force on the hoop is relatively small by comparison since the hoop rolls around the waist. A slight complication is that the hoop rotates…

A highly visual, inexpensive, straightforward laboratory experiment for the determination of the activation energy of a demulsification process is presented. The experiment uses low-density polyethylene (LDPE) beads to clearly mark the interface between an NaCl(aq) solution and isopropanol. The NaCl(aq)-isopropanol system is shaken to produce an…

The problem of a disc or cylinder initially rolling with slipping on a surface and subsequently transitioning to rolling without slipping is often cited in textbooks. Students struggle to qualitatively understand the difference between kinetic and static frictional forces--i.e., whereas the magnitude of the former is known, that of the latter can…

This study intended to confirm differences in peer relations between inquisitive and noninquisitive experiment class through social network analysis. In this study, inquiry science experiment classes for 30 students and noninquiry science experiment classes for different 30 students in the chapter named ‚Animals and Energy? of the second year of…

Online video experiments are a promising educational technology tool for science laboratory classes. In order to find optimal instructional designs and scenarios for using online video experiments, we need to study learners' experiences. This work describes implementation of an online interactive video experiment at the undergraduate introductory…

Enhancing the problem-solving skills of learners belonging to socio-economically disadvantaged groups is a great concern in general and particularly in the Indian context. Problem-solving skills are the most important skills of the 21st century for all learners to acquire necessary competencies. The main purpose of this work is to investigate the…