A simple setup was designed for a "time-of-flight" measurement of the sound speed in a metal bar. The experiment requires low cost components and is very simple to understand by students. A good use of it is as a demonstration experiment.

We safely remove the outer glass bulb from an incandescent lamp and burn up the tungsten filament after the glass is removed. This demonstration dramatically illustrates the necessity of a vacuum or inert gas for the environment surrounding the tungsten filament inside the bulb. Our approach has added historical importance since the incandescent…

An experiment with an electric transformer based on single coils shows how electromagnetic induction changes when the magnetic coupling between coils is adjusted. This transformer has two secondary outputs which are taken differentially. This is the basis for a widely used position transducer known as LVDT.

Because sound waves are such an abstract concept in physics, hands-on activities are often recommended to improve students' understanding and strengthen their knowledge. However, most schools do not have sufficiently sophisticated measuring instruments to perform sound wave experiments. Recently, researchers used smartphones as oscilloscopes,…

On July 19, 1969, Senator Edward Kennedy drove his vehicle off a low bridge on Chappaquiddick Island in Massachusetts. The vehicle sank in 2.1 m of water, coming to rest on its roof. According to Kennedy's version of events, he managed to escape from the submerged vehicle without injury, but his female companion, Mary Jo Kopechne, drowned without…

Laboratory exercises for undergraduate biochemistry students are described in which changes in sugar content during fermentation of the trendy beverage kombucha are analyzed by three methods: thin layer chromatography, a 3,5-dinitrosalicylic acid assay, and a standard commercial blood glucose meter. Each of the three analyses can be completed in a…

In conventional e/m experiments performed in undergraduate laboratories, generally a simple mechanical ruler is used to measure the radius of the circular trajectory of the electrons. But, the measurement error in this technique is mostly big and varies from one student to another. As an alternative to a mechanical ruler, we proposed a more…

A 3-week module incorporating the principles of green chemistry was developed for a large-enrollment, introductory organic chemistry laboratory course. An emphasis was placed on students planning their own experiments with the goal of obtaining a greener reaction (week 1). Students executed their designed experiments in week 2 and were given an…

The cannon boring experiment of Count Rumford, where eight kilograms of water were boiled by metal on metal friction, is investigated. Consideration of this dramatic demonstration can enrich classroom discussions of calorimetry, units of measure, elements, and thermodynamics. A section pertaining to use of the article in the classroom appears…

Heat and temperature concepts are found at all levels in the science curricula and are well-known for creating conceptual difficulties for learners. Students have difficulty understanding concepts related to heat, temperature, and thermal radiation. Inquiry-based pedagogies that can foster the learning of these difficult concepts are needed.…

A hands-on experiment to obtain atomic and ionic radii with lumps of metal and ionic compounds is reported here. The experiment is performed with industrial-grade typical metals (iron, copper, aluminum, and lead) and single-crystal lumps of ionic compounds (sodium chloride, potassium chloride, and potassium bromide). Students measure the dimension…

Here, students determine the total phenolic content in beers using the Folin-Ciocalteu assay. The Folin-Ciocalteu reagent is a yellow complex, in an alkaline medium; it reacts with phenols and non-phenolic reducing substances to form a blue complex. Quantitative analysis was carried out using absorbance measured at 765 nm (standard method) and…

Science festivals have been reported as an effective way to communicate science between scientists and the public; however, only a few studies have examined systematically and consistently how the festivals effect the public's conceptions of science. Moreover, few studies about science festivals for special education students are conducted. This…

Open-ended and inquiry-based experiments will make students more active in the learning environment, and so they play an active role in solving the problem. So, it is expected that especially classroom teachers will be more active in the laboratory environment. In this context, opinions of the classroom teachers about the science laboratory…

Due to resource limitations at predominantly undergraduate institutions, research opportunities for non-senior students can be limited. To provide opportunities for a variety of students to gain exposure to research, a course-based undergraduate research experience (CURE) was designed and conducted. Coupled inquiry was used to allow underclassmen…