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 paper, we present a physical modeling activity whose objective is to allow students to determine the differences between a disk and a sphere using pure scientific criteria. Thereunto, we reproduce the Sun-Earth-Moon system with low-cost materials and compare the illumination effects on the Moon considering two possible shapes for it (a…

In this work, the first experiment ever done to determine the age of the Earth is revisited. The benefits of its application at primary and secondary school levels are presented and discussed. In particular, emphasis is placed on the advantage of facing students with the challenges that scientists have had to overcome during the past three…

Twenty-two hundred years ago, the Greek scientist Eratosthenes measured the circumference of the Earth. This paper describes an experiment to replicate Eratosthenes' experiment with observers located in Australia and New Zealand. The most accurate circumference produced in the experiment described in this paper is 38,874?km, measured at Rosebud,…

Discusses the atmospheric characteristics of the earth and their implications for the development of life on earth-like planets. Indicates that the chance of life developing on other planets is not as great as men might have thought. (CC)

We are developing a new activity-based unit on global warming and the environment as part of the "Explorations in Physics Curriculum." We describe the current status of this unit, which focuses on helping students understand the greenhouse effect and its relationship to global warming. We outline several problems encountered in testing the unit…