A simple method is described for measuring liquid density based on stretching of the spring and equilibrium of weight and elastic force. The method involves placing a container with liquid under test on the spring causing a stretch of the spring that is directly proportional to the weight of the liquid. With this technique, the liquid density can…

Photogates play an important part of many of today's physics laboratory experiments. They signal when an infrared (IR) beam is interrupted, thus supplying the experimenter with important timing information. Currently photogates use an infrared photodiode (IR transmitter) and a phototransistor (IR receiver). User-built photogates have a weakness…

A solar eclipse provides a well-characterized reduction in solar radiation. Solar radiation is a driving factor in meteorological and climate models. Hence, solar eclipses provide a unique opportunity to do large-scale meteorological experiments by measuring the effects on temperature, pressure, and wind while the atmospheric conditions stay…

The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of…

Although it originates from the ancient Greeks, optics still arouses a lot of scientific interest, mainly due to the technological innovation associated with it. One of its most interesting applications is related to optical metrology and the characterization of materials through optical techniques. While some of these processes can be explained…

As an introduction to sound and vibration, the authors wanted their first-grade students to plan and conduct their own investigations. In this article, the authors share a series of investigations to help students explore the relationship between sound and vibration. By planning, creating, testing, adapting, and reflecting on the outcomes of the…

This paper addresses the fundamentals, structuring, and application of a Formative Dimensions for Green and Sustainable Chemical Education (Formative Dimensions -- GSCE) qualitative evaluation tool of experimental processes. This instrument was created considering the need to resignify laboratory practices in Chemical Education. Qualitative…

Recently, smart sensing/actuation paper has attracted significant interest due to its potential usage as a sustainable component in future electronics, robotics, and intelligent sensing devices. In acknowledging the importance of this topic for the engagement of students at the university level in conjunction with Industrial Revolution 4.0, it is…

Enzymes, enzymatic kinetics, and enzyme inhibition are topics covered in undergraduate biochemistry textbooks, having perceptible relevance to everyday life. The experimental use of enzymes involved in basic physiologic processes may be of utmost pedagogic interest because they bring evidence on how a significant number of drugs are used to…

This manuscript describes a laboratory exercise that allows students to use conductive atomic force microscopy (CAFM) for the analysis of electrodeposited, metallic structures. In addition to nanoscale electrical characterization with CAFM, this laboratory exercise also provides students with an opportunity to explore nanofabrication by…

In this laboratory teaching experiment, commercial cannabis oils were analyzed by undergraduate organic chemistry students using gas chromatography-mass spectrometry (GC-MS) to investigate three isomeric cannabinoids commonly found in cannabis products: cannabidiol (CBD), [delta][superscript 9]-tetrahydrocannabinol ([delta][superscript 9]-THC),…

In science classrooms, students usually see and work with data that's intended to tell them right away about the natural world. Students then often treat the data we provide to them as factual, rather than as a source of evidence (Duschl 2008; Sandoval and Millwood 2005; Berland and Reiser 2009; McNeill and Berland 2017; Hancock, Kaput, and…

In one of the Faraday's experiments an electric current is induced in a conducting loop when a magnet in front of it moves towards or away from the loop. While the direction of circulation of the electric current in the loop has only two options, it depends on three experimental conditions that generate eight cases. Even though the Faraday law or…

We describe here a low-cost experiment for introductory physics students where they compare the physical properties of aluminum and steel by means of cantilever oscillations. This, in turn, allows the students to improve their physical intuition about these materials. Further, the students can apply their physics and mathematics knowledge and…

It is well known that Newton's work on mechanics depended in a crucial way on the previous observations of Galileo. The key insight of Galileo was that one can analyze the motion of bodies using experiments and mathematical equations. One experimental observation that roughly emerges from this work in modern terms is that two objects of different…