Most springs do not simply obey Hooke's law because they are constructed to have an initial tension, which must be overcome before normal elongation occurs. This property, well known to engineers, is universally neglected in elementary physics courses. In particular, the standard simple harmonic motion experiment omits any discussion of this…

The pendulum has a great relevance in physics and it has been explored in educational papers from many theoretical or experimental points of view (see, for example, Refs. 1-12 and references therein). Here a method for the measurement of the gravitational acceleration with a large number of trials is presented; we assume that the systematic errors…

The conservation law of energy and momentum can be examined and demonstrated by a well-known collision experiment. In this experiment, several identical elastic balls are suspended from a horizontal frame. When the ball at one end is pulled aside and released, thus allowing it to swing like a pendulum, it hits the next ball. The outcome is…

A method for the synthesis of flufenamic acid, a nonstereoidal anti-inflammatory drug (NSAID) of the anthranilate family (fenams), is described as an experiment for the upper-division undergraduate organic chemistry laboratory. The key step is the formation of the diarylamine moiety of flufenamic acid by a novel reaction consisting of the coupling…

Although kinetics forms a foundational part of the chemical curriculum, laboratory experiences with the subject are often limited and lack relevance to the actual practice of chemistry. Presented is an inquiry-based lab focused on Michaelis-Menten kinetics, implemented in an upper-level, university physical chemistry laboratory. Student learning…

The conical pendulum is a topic theoretically approached in physics literature, but with little experimental activity developed due to the difficulty of reproducing the conical motion in ideal experimental conditions. This work consisted of studying the motion of a rigid conical pendulum using video analysis. The experimental results were used as…

What is the best way of discovering the underlying structure of a causal system composed of multiple variables? One prominent idea is that learners should manipulate each candidate variable in isolation to avoid confounds (sometimes known as the control of variables [CV] strategy). We demonstrate that CV is not always the most efficient method for…

Learning introductory quantum physics is challenging, in part due to the different paradigms in classical mechanics and quantum physics. Classical mechanics is deterministic in that the equations of motion and the initial conditions fully determine a particle's trajectory. Quantum physics is an inherently probabilistic theory in that only…

This study aims to measure Brewster's angle of glass and acrylic brick with an easy-to-obtain mobile application (app) by changing the tungsten light source to a red laser. The popularization of the smartphone has inspired many to use its various built-in sensors to carry out general physics experiments. Many others have adopted both a laser and a…

Experimentation is one of the important strategies used in engineering design to understand the relationship between relevant variables so that they can be manipulated to generate optimized solution for a particular problem or design. The understanding of students' experimentation strategies allows educators to help students improve their design…

One perennially important question for theories of sentence comprehension is whether the human sentence processing mechanism is "parallel" (i.e., it simultaneously represents multiple syntactic analyses of linguistic input) or "serial" (i.e., it constructs only a single analysis at a time). Despite its centrality, this question…

There is extensive disagreement as to whether preverbal infants have conceptual categories for different emotions (e.g., anger vs. disgust). In addition, few studies have examined whether infants have conceptual categories of emotions "within" the same dimension of valence and arousal (e.g., high arousal, negative emotions). The current…

A method for using electronic structure calculations to predict the standard molar enthalpy of combustion for hydrocarbons is presented. In this approach, simple geometry optimizations can be used to accurately compute the enthalpy of combustion within 3% of the experimental value using Hartree-Fock, MP2, or virtually any functional in density…

Gay-Lussac's law states that the pressure of an ideal gas is directly proportional to its absolute temperature if the volume is constant. Students observe this relationship by taking measurements on the pressure of gas in a flask or metal sphere at different temperatures and then extrapolate the data to estimate absolute zero. In our college…

Testing the reproducibility of an experiment is considered a good practice in science, and the possibility to reproduce an experiment is a condition of its scientificity. We investigate the ability of children to consider a counterintuitive phenomenon as reproducible. The study involved 62 5-year-old children from 4 classes. They were presented…