In this paper we consider the well-known experiment with the 'heavy' newspaper that breaks a stick that it is laid on. Using several appropriate control experiments we show that the currently invoked explanation using atmospheric pressure cannot be correct. We perform a theoretical analysis and propose a new explanation based on the rotational…

This paper takes a new look at a well-known physics demonstration--the Cartesian diver. A general overview is provided as well as some new twists on the old classic. A new version is proposed that can demonstrate some of the finer details of scuba diving. A hydrodynamic method of lifting sunken divers is presented.

The anomalous thermal expansion of water in the 0 °C-4 °C range is extremely important to life on Earth, but it is normally not presented experimentally in educational settings. This paper presents a simple experiment to explore the anomalous thermal expansion of water in the 0 °C-4 °C range and the heat exchange processes in natural bodies of…

In this article we consider a well-known simple, very accessible demonstration of surface tension with a small boat propelled by substances that change the surface tension of water. A simple quantitative evaluation is provided that matches well with experimental data. A modification to the experiment is proposed allowing it to continue for a long…

In this article we consider the well-known demonstration of friction by two interleaved books. We consider a factor that has not been part of the popular explanation--atmospheric pressure. We provide three control experiments to demonstrate the role of atmospheric pressure in the two-book experiment and an additional simple demonstration of the…

In this paper we consider the main properties of cylindrical lenses and propose several demonstrational experiments that can be performed with them. Specifically we use simple glasses full of water to demonstrate some basic geometrical optics principles and phenomena. We also present some less standard experiments that can be performed with such…

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…

In this paper we present two experiments to measure Boltzmann's constant--one of the fundamental constants of modern-day physics, which lies at the base of statistical mechanics and thermodynamics. The experiments use very basic theory, simple equipment and cheap and safe materials yet provide very precise results. They are very easy and…