CRISPR (also known as CRISPR-Cas9) is a powerful biotechnology tool that gives scientists unprecedented access to the genetic makeup of all living organisms, including humans. It originally evolved as an adaptive immune system in bacteria to defend against viruses. When artificially harnessed in the laboratory it allows scientists to accurately…

Electric charges and magnetic poles are often confused in the minds of students. It is convenient to remind them that they only interact when they are in relative motion. The force F on a charged particle q moving with velocity V in a magnetic field B is given by F = qVxB. By Newton's Third Law, the force on magnet producing the field B is equal…

The ammeter-voltmeter method is a general method for measuring electrical resistances that is widely used in the introductory physics laboratory, mostly for pedagogical reasons. Simultaneous readings of current (I) and voltage (V) allow the calculation of electrical resistance (R) using Ohm's law: R = V/I. It is implicitly assumed that electrical…

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…

The impact force and duration when one billiard ball collides head-on with another is estimated by assuming that the balls are connected by a spring. The results are compared with a measurement when a billiard ball collides with a heavy, rigid surface.

The use of the thermodynamic formalism in the investigation of biochemical reactions constitutes one of the key analysis in bioenergetics, and the first step in such analysis is the selection of the adequate reference state. For biochemistry majors, thermodynamic analysis based on the chemical reference state is used in Physical Chemistry courses,…

Herein, we describe a simple laboratory experiment to address nanomaterial synthesis, plasmon resonance, and its application to detect Cu[superscript 2+] in ultralow concentrations. The proposed experiment is very visual and appealing for chemistry students, especially the undergraduate-level chemistry major. In this experiment, the aggregation of…

The ballistic pendulum apparatus is a fairly ubiquitous element of the introductory physics laboratory, as the pendulum and launcher gun can be used together or independently to demonstrate a variety of concepts from conservation laws to projectile motion to the motion of a physical pendulum. In this work, we control the launch speed of the gun to…

Within physics education research (PER), inductive teaching strategies (e.g., inquiry-based teaching) have long been a goal. Yet others do not seem to be convinced that consensus exists with respect to the goals of physics education and identify three possible goals as: (1) to teach practical, factual knowledge, (2) to develop deep understandings…

In a traditional teaching approach, a physics course begins with mechanics, and generally the braking effect due to magnetic interactions is not mentioned among the various types of friction presented (static, sliding, rolling) because students will discover magnetism only in later chapters. In our didactic experience this traditional choice is…

The article describes research work that can help students observe and experimentally research the effects caused by the emission component of the filament current in fluorescent lamps' cathodes. When analysing the work of electronic devices--multi-purpose lamps that use thermionic emission--research usually focuses on the current caused by the…

Wide accessibility and a broad range of applications have made 3D-printers a commonplace tool in the science community. From tier-one research institutions to community public libraries and high schools, 3D-printers are being used to enrich STEM education through a variety of learning techniques and experiences. Reports of 3D-printed models for…

A method is described to measure the coefficient of restitution (COR) by dropping a ball on a piezoelectric disk. Multiple bounces can be observed at small drop heights, so the average COR over say ten bounces can be obtained from just one ball drop, without having to measure the bounce height or the bounce speed. The results show directly that…

The following story tells the details of the ketone body metabolism, focusing on the needs of the brain in prolonged fasting conditions. This literary composition highlights the use of ketone bodies as an important metabolic adaptation that avoids excessive protein degradation and allows for greater survival. The liver produces ketone bodies that…

One of the easily accessible results in elementary fluid mechanics is the so-called Torricelli's theorem (or law), which states that the velocity U[subscript th] of the fluid exiting from an orifice at depth "h" from the free surface of a container filled with fluid, is the same as the velocity of a free-falling body from rest over a…