Although the old problem of rotating liquid is described and solved in many textbooks and articles, the story still remains interesting. Intuitive understanding of the equipotential spatial surfaces is very difficult. This article is an attempt to present Newton's rotating tank in the light of the law of conservation of energy.

Purpose: The purpose of this paper is to recommend behavioral targets for future interventions to reduce greenhouse gas emissions at college campuses and to advise interventionists on how to choose between many potential behavioral targets. Design/methodology/approach: The authors used the community-based social marketing (CBSM) methodology over…

Newton's cradle is often discussed in science classrooms as a clear example of the laws of conservation of momentum and energy although it has been shown that this use is somewhat misleading. Approaches to understanding the behaviour of this apparatus are often over-simplified and deficient or over-complex and with little impact among teachers. In…

Newton's cradle is a well-known physics toy that is commonly used by teachers to demonstrate conservation laws in mechanics. It can also be used to investigate the physics of colliding objects, by recording motion of the balls on video film. Various experiments are described using 3-ball and 5-ball cradles, showing how different types of collision…

In a recent article in this journal, Shakur described an interesting problem where a bullet of mass "m" strikes a block of wood of mass "M" and projects the block upward. The same problem was considered earlier by Cowley et al. and others. The main question of interest is whether the block rises to a greater height if it is…

The work describes an analogy-based small oscillations analysis of a standard static equilibrium lab problem. In addition to force analysis, a potential energy function for the system is developed, and by drawing out mathematical similarities to the simple harmonic oscillator, we are able to describe (and experimentally verify) the period of small…

This study compares the scientific and alternative conceptions of energy and momentum of university first-year science students in Ethiopia and the US. Written data were collected using the Energy and Momentum Conceptual Survey developed by Singh and Rosengrant. The Concentration Analysis statistical method was used for analysing the Ethiopian…

The first recorded experiments describing the phenomena made popular by Newton's cradle appear to be those conducted by Edme Mariotte around 1670. He was quoted in Newton's "Principia," along with Wren, Wallis, and Huygens, as having conducted pioneering experiments on the collisions of pendulum balls. Each of these authors concluded that momentum…

An interesting, quick, and inexpensive lab that we do with our students is to tape one end of a string just less than halfway around the back side of a uniform solid cylinder m[subscript 1] and attach the other end of the string to a mass m[subscript 2] that is below a pulley (Fig. 1). Data can be collected using either an Ultra Pulley (Fig. 2) or…

Studied the development of the concepts of energy conservation and entropy in 5- to 15-year-old children. Energy conservation was not well understood until about age 15. Entropy was understood by 9- to 15-year-olds when the concept was illustrated by the gradual mixing of differently colored, rolling marbles. (Author/DB)

Outlines the use of the toy popularly known as Newton's Cradle or Newton's Balls in illustrating the laws of conservation of momentum and mechanical energy. Discusses in detail the joint effects of elasticity, friction, and ball alignment on the rate of damping of this apparatus. (JRH)

Presents an experiment that demonstrates conservation of momentum and energy using a box on the ground moving backwards as it is struck by a projectile. Discusses lab calculations, setup, management, errors, and improvements. (JRH)

Presents exercises that analyze the additive property of energy. Concludes that if a body has more than one component of energy depending on the same physical quantity, the body's total energy will be the algebraic sum of the components if a linear relationship exists between the energy components and that physical quantity. (JRH)

Discusses a series of experiments to establish a significance of temperature difference in rates of cooling, to illustrate the connection between energy transfer and the consequent temperature changes for thermally connected systems that are not in equilibrium. (MKR)

Explores how the apparent loss of energy in inelastic collisions may be understood by considering a simple model of two rigid balls connected by a spring. Includes a numerical simulation of this and an extension to include Newton's Cradle. (DDR)