A classical mechanical structure with an internal degree of freedom is shown to reflect off a potential well. Such behavior is impossible for point-like or rigid classical particles. This numerical study provides insight for students studying internal energy and degrees of freedom.

Apparatus catalogues of the first half of the 20th century contain a number of clever and simple devices for measuring the index of refraction of a liquid. In some cases students can put together one of these pieces of apparatus and then make their own measurements. The Gilley board was one of the devices that caught my eye, and I would like to…

Students may have some confusion understanding certain physical concepts and principles because of their abstract nature. Using analogies is one of the useful methods to help them more easily grasp abstract concepts to promote conceptual understanding. Bilaloglu classified analogies in four groups: (a) simple analogies, (b) storified analogies,…

The phenomenon of emerging water jets from the holes of containers has been extensively studied; nevertheless, it continues to inspire researchers and teachers. The main aspects of the recent studies concern: the range of the jets trajectories; the extension of Bernoulli's equation, of which Torricelli's expression represents an ideal situation,…

November 10, 2015, marked the 40th anniversary of the sinking of the "S. S. Edmund Fitzgerald," a Great Lakes bulk cargo freighter that suddenly and mysteriously sank during a severe winter storm on Lake Superior. A year after the sinking, Canadian folksinger Gordon Lightfoot wrote and recorded the ballad "The Wreck of the 'Edmund…

After the discovery that superconducting magnets could levitate diamagnetic objects, researchers became interested in measuring the repulsion of diamagnetic fluids in strong magnetic fields, which was given the name "The Moses Effect." Both for the levitation experiments and the quantitative studies on liquids, the large magnetic fields necessary…

Each year our physical science class for pre-service elementary teachers launches water-powered rockets based on the activity from NASA. We analyze the rocket flight using data from frame-by-frame video analysis of the launches. Before developing the methods presented in this paper, we noticed our students were mired in calculation details while…

The hydromonochord is a horizontal vibrating string that just makes contact with the surface of a water bath. The motion of the string sets up a pattern of swirls on the surface of the water, thus complementing the usual pattern of nodes and antinodes. The device is based on the traditional monochord. A water basin (Fig. 1) has two slits in the…

In this work, an inexpensive 10-gallon glass aquarium was used to study wave motion in water. The waves travel at speeds comparable to a person walking ([approximately]1 m/s). The scale of the motion allows for distances to be measured with a meterstick and for times to be measured with a stopwatch. For a wide range of water depths, standing waves…

Vortex flow, from millimeter to kilometer in scale, is important in many scientific and technological areas. Examples are seen in water strider locomotion, from industrial pipe flow (wastewater treatment) to air traffic control (safe distance between aircrafts on a runway ready for takeoff) to atmospheric studies. In this paper, we focus on a…

This paper describes a very simple exercise using an inverted test tube pushed straight down into a column of water to determine the free-fall acceleration "g". The exercise employs the ideal gas law and only involves the measurement of the displacement of the bottom of the "diving bell" and the water level inside the tube with respect to the…

The tendency of fluids to follow, in certain conditions, curved profiles is often referred to as the Coanda effect. A simple experiment modeling the common teapot effect, the curling of the liquid around the beak when it is poured, can be used in the classroom to illustrate simple dynamic principles and basic fluid dynamics concepts as well.

I have found that students easily understand that a measurement cannot be exact, but they often seem to lack an understanding of why it is important to know "something" about the magnitude of the uncertainty. This tends to promote an attitude that almost any uncertainty value will do. Such indifference may exist because once an uncertainty is…

Students become deeply involved in physics classes when spectacular demonstrations take over from abstract and formal presentations. In this paper we propose a simple experimental setup in which the wave behavior of light can be made spectacularly evident along the whole path of the light beam in a practically unlimited number of configurations.…

Here is a quick way to measure the index of refraction of water using the phenomenon of total internal reflection.