A loop-the-loop experiment is described to show how sliding friction affects motion of the ball. Conservation of energy can be used to explain the basic physics, but significant energy loss is observed in practice and expands the usefulness of this apparatus as a teaching tool.

The problem of an electrically charged pendulum above a grounded conducting surface is examined using traditional analyses, such as forces, energy, and torque. The system was numerically modelled using a finite difference method and analysed. A number of classroom activities have been suggested.

A loop-the-loop experiment usually involves a ball rolling around a vertical loop. A different version of the experiment is described where a nut was allowed to slide around a vertical loop. In both experiments there is a large decrease in kinetic energy when the ball or the nut first enters the loop.

When any object, such as a glass of water, a greenhouse or the Earth's atmosphere, stays at a steady temperature, the amount of energy entering the object is equal to the amount of energy leaving it. This is considered in equilibrium. This equilibrium changes when the amount of energy entering does not equal the amount of energy leaving.…

The Mayan city of Chichen Itza is full of legends and mysticism. There, in the temple of Kukulkan, in front of a great pyramid with 91 central staircases, an interesting physical-acoustic phenomenon occurs that has fed mythical stories attributed to the Mayas. When clapping your hands in front of the steps, the echo sounds very different from the…

For single-slit diffraction and double-slit interference experiments, commercially made slits can be the most expensive parts, especially since the prices of laser pointers have become very low. One option is to use a razor blade to cut slits in either paint or electrical tape on microscope slides. However, this takes practice, and there is some…

In this paper I describe an interactive Gauss's law computer simulation using the GlowScript programming environment. The simulation calculates a point charge's electric field at locations on the surface of a Gaussian cube and displays the electric field in GlowScript's 3D graphics window. The point charge can be moved, and the electric field…

Student misconceptions of the double-slit experiment (Fig. 1) are abundant. The most common ones that we observe include: (1) belief that constructive interference requires both pathlengths to be integer multiples of the wavelength ("L[subscript 1] = n[subscript 1][lambda]" and "L[subscript 2] = n[subscript 2][lambda]") rather…

Drop Tower Physics (DTP) is composed of a set of experiments using standard physics lecture demonstration equipment, such as a pendulum, mass spring oscillator, and so forth, while videotaping them as they fall freely in the Dryden Drop Tower in Portland, OR. An article published in "The Physics Teacher" illustrated the behavior of a…

The conical pendulum is a classic introductory physics problem for teaching circular motion--a topic about which students frequently carry alternative conceptions. As teachers provide lessons to untangle these conceptions, it is good to allow students to practice their new knowledge in varied settings. This is one possible experiment that builds…

A smartphone magnetometer is used to record the magnetic field of a freely falling point dipole magnet. The recorded magnetic field vs. time data are analyzed in accordance with the spatial dependence of the magnetic field to calculate the acceleration due to gravity g. The experiment gives local g to be 9.79 ± 1.9% m/s[superscript 2].

Students experience current electricity every day in our wired world, yet the circuit problems that students work through in physics class can seem far removed from the common experience of switching on a light bulb. However, current electricity provides many opportunities to engage students in hands-on learning. Through circuit construction,…

Discovering concepts through observation, exploration, and constructing scientific explanations of phenomena is best practice in science education. Instead of following lab procedures to verify a known answer or solution, involve students in the work of science. Begin by presenting a phenomenon to engage students in scientific inquiry and uncover…

Prompt determination of the positive or negative signs of charged objects promotes students' understanding of electrostatics and motivates them to learn more about this field of physics. We developed a low-cost (about US$5) and easy-to-use device for checking the signs of the static charges in objects. It consists of two easy-to-build circuits,…

This study aims to explore the mental models of students about suspending objects in liquid fluid. The study used a descriptive qualitative method and implemented cross-sectional approach. It involved 57 students from grade 5 of elementary school to fourth-year prospective physics teachers. The data collection used a test consisting of twenty-six…