The ideal gas law, "PV = nRT," is one of the simplest physical laws in nature that is introduced to students as early as in high school and first year in college. In this equation, "P" stands for pressure, "V" is the volume, "n" is the amount expressed in mole, "T" is the temperature in Kelvin…

In this article we present a simple technique for determination of the Young modulus of the material of a metallic ruler using it as a cantilever. This method employs with a slide potentiometer and a digital multimeter. The linear region of potentiometer resistance which is calibrated in terms of length has been used to record the load vs.…

The refractive index of a liquid is known to depend strongly on the temperature gradient of liquids. When a laser beam passes through a transparent material going through thermal diffusion, the light projected onto a screen will be displaced in relation to the thermal diffusivity. A simple apparatus is used to measure the time evolution t of the…

Granular flows appear frequently in the natural world and in civil engineering applications. These flows can exhibit features which are surprising and counter-intuitive and are often used to test the limits of the classical continuum approximation for modelling of fluid flows. An important sub-class of the granular flows are the gravity-driven…

Teaching the noncommutativity of the product of matrices to high school or college level students is a difficult task when approached from a purely formal perspective. The aim of this paper is to present a simple experimental activity for teaching the noncommutativity of the matrix product, based on the Jones calculus, a mathematical formalism for…

We present an experiment designed to study standing waves in a tube with one closed end. Two smartphones are used, one to emit a sound signal with a chosen frequency and another equipped with a microphone to detect the sound pressure level inside the tube. Due to the finite diameter of the tube, the standing wave node (or antinode) appears…

In this paper we present a study on the capillary action of water in a glass tube. It is a well-known phenomenon that the rise of a water column in the capillary is governed by parameters such as surface tension of water, radius of the tube, density of water and acceleration due to gravity. The interdependence of the parameters gives rise to the…

Old physics textbooks give us a great opportunity to learn about the history of science and rediscover different methods to teach physics to our students. There are many disused and forgotten experiments in them, but these can still be very useful to affirm and understand physics. This is the case of an instrument used in the 19th century to…

[This paper is part of the Focused Collection on Instructional labs: Improving traditions and new directions.] In this paper, we describe the results of a research project whose goals were to (1) develop and implement video-based experimental investigations using the Investigative Science Learning Environment (ISLE) approach and (2) study how…

This paper demonstrates the use of a smartphone's sensors in recording experimental data for investigating the large angle of a physical pendulum. The smartphone (iPhone 5s) was attached to a beam to record simultaneously both the angular position and the angular speed of the beam oscillating about the pivot. The period and phase space of the…

By building a schlieren optical system, the visualization of a 40 KHz sound wave is realized. By using the schlieren system, the demonstration of acoustic reflection, interference and diffraction can be easily realized. At the same time, the visual acoustic field provides another simple way for the measurement of sound velocity. In this paper, the…

A common procedure when conducting physics experiments is to repeat a measurement several times to calculate the mean and standard deviation. That might be the only instruction we give to students as a means to minimize random errors. However, that technique does not guarantee that the answer will be correct. It might give the same wrong answer…

Kundt's tube is a popular experiment commonly used in schools, in which standing sound waves are made visible inside a glass tube. A fine powder is stirred up in areas of high sound particle velocities, so that one can measure the wavelength of the sound waves by examining the patterns created. In this way, the 'invisible' can be made visible.…

This work presents the design of an inexpensive electronic system to measure water temperature and generate an experimental data set used to verify the fitting between experimental and theoretical curves of a water-cooling process. The cooling constant is computed with three different theoretical methods to check their efficiency and this approach…

Light spectrum dispersion is an exciting subject in science because of its beautiful atmospheric colour phenomenon which attracts students. However, to see the phenomenon is not easy since it needs a spectrometer, which is commonly expensive. Therefore, the present study aims to describe a low-cost spectrometer for investigating lighting spectrum…