A container was placed on top of a piece of white paper, and a pin positioned so that it vertically touched an outside wall of the container. Students were asked to predict the image of the pin when it was observed from the top of the container. Two scenarios of either an empty container or a container completely filled with water were considered…

We have developed much simpler cloud chambers that use only ice and cooking salt instead of the dry ice or ice gel pack needed for the cloud chambers produced in our previous work. The observed alpha-ray particle tracks are as clear as those observed using our previous cloud chambers. The tracks can be observed continuously for about 20?min, and…

The purpose of this paper is to introduce students of science and engineering to the orbital lifetimes of satellites in circular low Earth orbits. It is only necessary to know about classical mechanics for this calculation. The orbital decay of satellites is due to the interaction of the satellite with the surrounding gas, atmospheric drag.…

A method to determine the temperature dependence of copper wire resistance is described in this paper.

Experiments are described on collisions between two billiard balls and between a bat and a ball. The experiments are designed to extend a student's understanding of collision events and could be used either as a classroom demonstration or for a student project.

In the present paper we suggest an original physical explanatory model that explains the mechanism of the sound amplification process in a stethoscope. We discuss the amplification of a single pulse, a continuous wave of certain frequency, and finally we address the resonant frequencies. It is our belief that this model may provide students with…

A simple mathematical formulation of Mach's principle is given based on a century of investigation into inertia, and used to check the results of Newton's famous bucket experiment.

We present a general physics laboratory exercise that centres around the use of the electrocardiogram sensor as an application of circuits and electronic signal filtering. Although these topics are commonly taught in the general physics classroom, many students consider topics such as alternating current as unrelated to their future professions.…

This paper gives the solution and analysis of projectile motion in a vacuum if the launch and impact heights are not equal. Formulas for the maximum horizontal range and the corresponding angle are derived. An Excel application that simulates the motion is also presented, and the result of an experiment in which 38 secondary school students…

Entertaining and educational experiments that can be conducted in a water park, illustrating physics concepts, principles and fundamental laws, are described. These experiments are suitable for students ranging from senior secondary school to junior university level. Newton's laws of motion, Bernoulli's equation, based on the…

This paper describes an interactive tool for analysis of data from the ATLAS experiment taking place at the world's highest energy particle collider at CERN. The tool, called HYPATIA/applet, enables students of various levels to become acquainted with particle physics and look for discoveries in a similar way to that of real research.

The history of science remembers more than just formal facts about scientific discoveries. These side stories are often inspiring. One of them, the story of an unfulfilled death wish of Jacob Bernoulli regarding spirals, inspired us to look around ourselves. And we saw natural spirals around us, which led to the creation of a Hooke's…

A Cartesian diver can be used to measure the surface tension of a liquid to a certain extent. The surface tension measurement is related to the two critical pressures at which the diver is about to sink and about to emerge. After sinking because of increasing pressure, the diver is repulsed to the centre of the vessel. After the pressure is…

Theory predicts that an egg-shaped body should rest in stable equilibrium when on its side, balance vertically in metastable equilibrium on its broad end and be completely unstable on its narrow end. A homogeneous solid egg made from wood, clay or plastic behaves in this way, but a real egg will not stand on either end. It is shown that this…

A simple, and popular, demonstration of the greenhouse effect involves a higher temperature being observed in a container with an elevated concentration of CO[subscript 2] inside than in a container with just air enclosed, when subject to direct light. The CO[subscript 2] absorbs outgoing thermal radiation and causes the air inside the container…