Students determine the iron mass in dietary supplements using four colorimetric assays. These colorimetric assays were selective for Fe[superscript 3+]. It was complexed by thiocyanide, salicylate, gallic acid, and Fe(CN)[subscript 6][superscript 4-], forming blood-red, red, violet, and blue complexes, respectively. The [lambda][subscript max] of…

Newton's cradle is a well-known physics toy that is commonly used by teachers to demonstrate conservation laws in mechanics. It can also be used to investigate the physics of colliding objects, by recording motion of the balls on video film. Various experiments are described using 3-ball and 5-ball cradles, showing how different types of collision…

The vertical bounce of a plastic egg was investigated by dropping the egg on a horizontal surface and filming the result with a video camera. If the egg is dropped on one end then it bounces just like a spherical ball. If the top end of the egg is pointing forwards or backwards when it lands on the surface, or if the egg is spinning when it lands,…

In this paper, we present a demonstration of Ohm's law on a spreadsheet. Students can perform an experiment of Ohm's law like they perform in laboratories. The only difference is that the apparatus is virtual. The students record readings of current through the circuit and potential difference across a resistor. A graph is drawn between I and V to…

Although nearly everyone is familiar with colors from an early age and the fundamentals of color mixing are taught at various abstraction levels throughout kindergarten to high school, we repeatedly observe that our student teachers in physics have problems in explaining the subject. Therefore, we propose an experimental setup that focuses on the…

In recent years, with the more powerful functions of smartphones, the use of sensors integrated by mobile phones as an auxiliary tool for physical experiment teaching has become more popular. Combined with the related mobile phone apps, people easily can develop and expand the physical experiment contents of mechanics, optics, acoustic phenomena,…

Students should have a strong conceptual understanding of the connection between force and acceleration before they start working with applications and problem solving. This has been discussed in the literature. During these days of flipped classroom instruction, an at-home activity could be especially valuable. I will describe an experiment with…

Physics instructors recognize the value of kinesthetic experience in learning fundamental physics concepts. We describe a kinesthetic experiment appropriate for both college and high school physics students. The experiment helps students achieve an intuitive understanding of Newton's second law in a way they find quite enjoyable. It was devised by…

The study of buoyancy becomes very interesting when we measure the apparent weight of the body and the liquid vessel weight. In this paper, we propose an experimental apparatus that measures both the forces mentioned before as a function of the depth that a cylinder is sunk into the water. It is done using two load cells connected to an Arduino.…

Newton's laws of mechanics are a cornerstone in the development of modern science and its learning can be the very first opportunity for students to defy their common sense perceptions and replace them with a more robust world view. However, despite their fundamental importance, many studies demonstrate how difficult is the true comprehension of…

Charging a capacitor with a photovoltaic module is an experiment which reveals a lot about the modules characteristics. It is customary to represent these characteristics with an equivalent circuit whose elements represent its physical parameters. The behavior of a photovoltaic module is very similar to that of a single cell but the electric…

Cosmic expansion is an important concept in astronomy. For ease of understanding, astronomers generally draw an analogy between cosmic expansion and the expansion of a spherical surface in 3D space. This study theoretically and experimentally investigates the laws governing the motion of particles on the surface of a balloon during expansion.…

The classroom jumping ring demonstration is nearly always performed using alternating current (AC), in which the ring jumps or flies off the extended iron core when the switch is closed. The ring jumps higher when cooled with liquid nitrogen (LN2). We have performed experiments using DC to power the solenoid and find similarities and significant…

Electrochemistry is primarily taught in first-year undergraduate courses through batteries; this lab focuses instead on corrosion to apply electrochemical concepts of electrolytes, standard reduction potentials, galvanic cells, and other chemistry concepts including Le Chatelier's Principle and Henry's Law. Students investigate galvanic corrosion…

Students are well aware of the effect of the deflection of sports balls when they have been given a spin. A volleyball, tennis, or table tennis ball served with topspin results in an additional downward force that makes the ball difficult to catch and return. In soccer, the effect of sidespin causes the ball to curve unexpectedly sideways,…