Calculations are presented showing that the usual 'faster than g' demonstration has a surprising property. That is, a rod hinged at its bottom end rotates at an exponentially increasing rate until it falls with maximum vertical acceleration, unlike an object that falls freely by gravity alone. If the rod is hinged at its top end and released from…

A simple experiment is described to compare the descent time between two vertically separated points when an object slides down tracks of varying shape. A surprising result is that the descent time is shortest when it follows a circular track rather than a cycloidal track. Cycloidal tracks are usually predicted to result in the shortest descent…

The analysis, calculations and graphical charts presented here in this paper are based directly on a recently published paper by the first two of the above-named authors. In the present paper, it is clearly demonstrated that all of the following nine (or eleven including the centripetal acceleration and total mechanical energy) principal physical…

This study focuses on the experimental demonstration of the definition of kelvin using a triple point of water (TPW) cell and estimates the measurement uncertainty. The first part of this article is to construct the measurement setup and perform the measurements. The second stage is related with the calculation of uncertainty according to guides…

The calculation of the magnetic field produced by a loop current using the Biot-Savart law is a very typical exercise in introductory university physics. However, the cases studied are limited, in most textbooks, only the circular arrangement is treated. In this article, we calculate the magnetic field of an elliptical loop current along an axis…

An experiment using the volumetric flux of a water stream was used to find the initial velocity of the water as it performs parabolic motion. The trajectories were measured with different initial velocities, comparing the maximum height and range values with the theoretical calculations. The closeness of the measured values to the calculations…

A well known physics problem is to calculate the friction forces required to support a ladder against a wall. A more tractable problem is to calculate the friction forces needed to support an inclined beam on a ball or a cylinder. In the latter case there are three rather than two points of sliding support. Measurements and calculations are…

This work presents the design of an inexpensive electronic system to measure water temperature and generate an experimental data set used to verify the fitting between experimental and theoretical curves of a water-cooling process. The cooling constant is computed with three different theoretical methods to check their efficiency and this approach…

This work shows the redesign of an elemental experience based on the Helmholtz resonator using 3D printing. A Helmholtz resonator is based on a volume and at least one opening that can include a tube or not. The air column inside the tube can be considered the mass of the system, whereas the volume represents the system's stiffness. Due to these…

A number of useful and interesting exercises regarding nucleus and nuclear fission are performed to make these concepts more understandable to high school or even college students.

A solid ball placed on a rotating turntable is known to roll slowly around a circular path, at a speed 3.5 times slower than the turnable itself. If the ball is located in a straight track across a diameter of the turntable, then it accelerates rapidly to the edge. Both effects were filmed in slow motion using a video camera and a cake decoration…

Interaction forces between magnetic fields and current loops play a central role in the theory of magnetism. This work describes a reasonably simple and cheap experiment for demonstrating this issue: the force on a thin coil due to a nearby cylindrical magnet. The magnitude of the force as well as its attractive/repulsive character is comfortably…

An original approach using three appropriate Pythagorean triangles is presented for the detailed mathematical analysis of an ideal conical pendulum. The triangles that are used in this analysis relate specifically to the physical dimensions of the conical pendulum, the magnitudes of the forces acting during the conical pendulum motion and a…

We discuss the limits of the equation of the period of a simple pendulum, T[subscript s] = 2[pi][square root]l/g, frequently used in high-school and university classrooms to measure the acceleration of gravity. We evaluate the relative error in determining the acceleration of gravity with this simple equation instead of a more realistic one,…

An elementary-level physics approach is used to calculate a number of interesting and useful quantities related to nuclear explosions. The set of eight exercises deals with nuclear fission fragments, the variation of fissile nucleus density in a fissioning nuclear device core with time, and the fireball.