We discuss the limits of the equation of the period of a simple pendulum, T[subscript s] = 2[pi][square root]l/g, frequently used in high-school and university classrooms to measure the acceleration of gravity. We evaluate the relative error in determining the acceleration of gravity with this simple equation instead of a more realistic one,…

A glass of water covered with a disk with a hole in it can be turned upside down without spilling the water in the glass, provided the hole is small enough and the disk is pressed against the rim of the glass. A quasistatic numerical simulation based on hydrostatic pressure and surface tension of water was used calculate the critical hole diameter…

In a paper (posthumously) co-authored by Isaac Newton himself, the primacy of geometric notions in pedagogical expositions of centripetal acceleration has been clearly asserted. In the present paper we demonstrate how this pedagogical prerogative can inform the design of an experiment involving an accelerometer-equipped smartphone rotating…

It is generally agreed that making real-world connections in mathematics teaching increases students' motivation and interest and contributes to meaningful and permanent learning. In this paper we propose a simple and fast activity to find a rectangular hyperbola in real life and we show how to operate the data to retrieve a straight line. Since…

Two pendula of length "l," suspended from points separated by a horizontal distance a, can be joined in a trapezium configuration by linking the bobs with a light inextensible string of length b < a. Here we introduce this 'trapezoidal pendulum' as a charming and novel oscillatory system suitable for introductory physics laboratories.…

In this study, the spring constant was determined within the scope of Hooke's law. For this purpose, an Arduino MEGA, an HC-SR04 Ultrasonic Distance Sensor, and a 1 kg Load Cell Mass Sensor was used. Sensors and microprocessor are mounted on a plane. One end of the spring is mounted on the force sensor, and a wooden rod, perceived by the distance…

This article describes an experiment that can be done in the classroom in a simple way, with the support of a "homemade" device or as a laboratory practice with the support of PASCO equipment. Through a theory-practice sequence, kinematic and dynamic equations were checked with qualitative and quantitative analysis, emphasizing the…

There are many physics experiments with long time scales such that they are usually neither shown in the physics class room nor in student labs. However, they can be easily recorded with time-lapse cameras and the respective time-lapse videos allow qualitative and/or quantitative analysis of the underlying physics. Here, we present some examples…

This study is aimed at first introducing a well-known discrepant event; inseparable phone books and second, turning it into an experiment for high school or middle school students. This discrepant event could be used especially to indicate how friction force can be effective in producing an unexpected result. Demonstration, discussion, explanation…

If we drop a magnet through a coil, an emf is induced in the coil according to Faraday's law of electromagnetic induction. Here, such an experiment is done using expEYES kit. The plot of emf versus time has a specific shape with two peaks. A theoretical analysis of this graph is discussed here for both short and long cylindrical magnets.…

A classical experiment used to introduce the concept of body inertia, breaking of a thread below and above a hanging weight, is described mathematically and presented in a new way, using force sensors and a computer system.

In this paper we present three different methods for testing Bernoulli's law that are different from the standard "tube with varying cross-section." They are all applicable to high-school level physics education, with varying levels of theoretical and experimental complexity, depending on students' skills, and may even be…

For physical measurements, the compositions of solutions, especially electrolyte solutions, are expressed in terms of molality rather than mole fractions. The development of the necessary thermodynamic equations directly in terms of molality is not common in textbooks, and the treatment in the literature is not very systematic. We develop a…

The heterogeneous equilibrium of the solubility of calcium hydroxide in water is used to predict both its solubility product from solubility and solubility values from solubility product when inert salts, in any concentration, are present. Accepting the necessity of including activity coefficients to treat the saturated solution of calcium…

Everyone enjoys seeing the cloudy white fog generated when solid carbon dioxide (dry ice) is placed in water. Have you ever wondered what physical and chemical processes occur to produce this fog? When asked this question, many chemical educators suggest that the fog is produced when atmospheric water vapor condenses on cold carbon dioxide gas…