A single-slit diffraction experiment in an introductory physics laboratory is generally comprised of a rectangular slit and a laser source. The laser beam is sent to the slit producing the well-known diffraction pattern on the screen. This paper proposes a simple modification of the single-slit diffraction experiment to increase student attention…

We have developed new rotors that can be classified into three groups by changing the rotors used in simple motors into various types. Group I has a semicircular shape rather than a perfect circle or square shape, group II has a structure consisting of several closed circles on one plane, and group III has a three-dimensional shape. We wanted to…

The trajectory of a ball rolling across an inclined plane was recorded on video film to determine if it followed a parabolic path as others have suggested. The challenges in this case were (a) to determine the magnitude and direction of the friction force on the ball, (b) to determine the effect of the friction force on the trajectory and (c) to…

Astronomy is one of the few sciences where the data (star-light) can be seen by all. Yet, there is a disconnect between a typical undergraduate lecture and, for example, where a planet may be in the sky and how to observe it. With the advent of moderate cost, high-quality 'back-garden' astronomy, and standard computers powerful enough to produce…

An ordinary soap bubble immersed in a pure carbon-dioxide atmosphere, created e.g. by sublimating chunks of dry ice (solid CO[subscript 2]), will expand within a few minutes to a volume exceeding the original one with a factor of almost ten. Considering that the bubble simultaneously experiences a cooling of ~30 ?C one would perhaps expect a tiny…

Spectrometers play a decisive role in the education of A-level and/or under-graduate students in the field of natural sciences. They are capable to demonstrate atomic emission, transmission, reflection and fluorescence spectra, but can be used for wavelength filtering, as well. Here, we present a do-it-yourself spectrometer setup based on a…

This study has proposed a simple method to show the convective heat transfer. The object in this study is an air conditioner (AC) as a simple case of convection. In addition, AC is also easy to find in the class because most classrooms in Indonesia installed AC. Usually, a visualization needs special software (i.e. MatLab or others) and good…

A cost-effective method has been developed with utmost efficiency for the determination of density of a liquid. The experimental setup for this purpose is a Polyvinyl chloride (PVC) cylinder fitted with an overflow spout, a volume measuring cylinder, a wooden block along with a hook and a known mass taken from scientific weight box. For this…

Special Relativity introduces students to Modern Physics, whose importance in the high school is increasing. Nevertheless its teaching and learning is a critical issue. Different solutions have been developed to overcome the encountered difficulties. In this paper we describe the spacetime globe, a mechanical instrument that allows to experience…

The falling rod paradox, i.e. the fact that the tip of an almost horizontal rod falls with an acceleration 'higher than g', when the other end is hinged or supported, is a popular physics demonstration. It can be visualized by placing e.g. a coin on the tip of the rod and fixing a cup next to the coin. When the rod is released the free-falling…

The dynamic study of pendulum systems is considered an indispensable subject for physics and mechanics students in colleges and high schools. In this paper, a detailed methodology is given concerning the use of smartphones in pedagogical practical work for studying the dynamics of pendulum systems. Whereas, three aspects have been discussed…

Electromagnetic (EM) waves are indispensable in modern telecommunications. Despite their essential role in modern technology, EM waves are considered to be an abstract concept by many students. In this activity, an inexpensive two-coil system was constructed in a teaching laboratory and used to demonstrate information transfer by non-sinusoidal EM…

In order to fix some important concepts of Fundamental Physics, either because they are not usually discussed in depth in theoretical classes and much less at laboratories, or because they are not sufficiently developed in textbooks, it is more effective not to tackle them directly, but to propose a mental or practical experiment to attract the…

In this work, a simple rocking pendulum, in a circular arc shape, is presented. The idea is to put a rigid arc on a clean flat surface of glass and leave it to oscillate under the effect of a little impulse. Then, the periodic time of this arc pendulum's motion is experimentally determined. The mathematical analysis of the arc's motion is derived…

If a ball rolls in a circular path on a horizontal surface at constant speed then its horizontal rotation axis changes direction with time. A simple experiment is presented showing that the torque applied to the ball is equal to the rate of change of its angular momentum, even though the magnitudes of its angular velocity and angular momentum…