Motion in a circle troubled Newton and his contemporaries and troubles students today. Presents a clear presentation of certain aspects, particularly centripetal acceleration and centrifugal force. (Author/MM)

The effects of 2 weeks of no, general, and task-related enhanced movement experiences on 8- to 12-week-old infants' (N=30) hand and foot interactions with objects were assessed using standard video and motion analysis. For hand object interaction ability, general and task experience led to greater success than did no experience, and task…

In speech research, it is often desirable to assess quantitatively the variability of a set of speech movement trajectories. This problem is studied here using synthetic trajectories, which consist of a common pattern and terms representing amplitude and phase variability. The results show that a technique for temporal alignment of the records…

Prior studies of time-to-contact (TTC) focused on judgments of unoccluded approaching objects. P. R. DeLucia, M. K. Kaiser, J. M. Bush, L. E. Meyer, and B. T. Sweet (2003) showed that partial occlusion decreases an object's optical size and expansion rate and that the value of tau derived from the reduced optical size (relative rate of accretion;…

In 4 experiments, the authors varied the extent and nature of participant movement in a virtual environment to examine the influence of action on estimates of geographical slant. Previous studies showed that people consciously overestimate hill slant but can still accurately guide an action toward the hill (D. R. Proffitt, M. Bhalla, R.…

The Wing-Kristofferson model (A. M. Wing & A. B. Kristofferson, (1973a, 1973b) decomposes the variance of isochronous finger tapping into 2 components: a central clock component and a peripheral motor component. The method assumes that there is no drift in the intertap intervals. A new method is introduced that further decomposes the clock…

Modern visualization techniques in science education present a challenge of sorting out the contributions of perception to understanding science. These contributions range over degrees to which perception is influenced by belief (including systematic sets of beliefs which comprise scientific theories) and social setting. This paper proposes a…

Kuhn underlined the relevance of Galileo's gestalt switch in the interpretation of a swinging body from constrained fall to time metre. But the new interpretation did not eliminate the older one. The constrained fall, both in the motion of pendulums and along inclined planes, led Galileo to the law of free fall. Experimenting with physical…

Prehension movements of the right hand were recorded in a right-handed man (AC), with an injury to the left posterior parietal cortex (PPC) and with a section of the left half of the splenium. The kinematic analysis of AC's grasping movements in direct and perturbed conditions was compared to that of five control subjects. A novel effect in…

Real-world situations involve attending to spatially extended objects, often under conditions of motion and high processing load. The present experiments investigated such processing by requiring observers to attentionally track a number of long, moving lines. Concurrently, observers responded to sporadic probes as a measure of the distribution of…

We present a simple activity that permits students to determine the coefficient of restitution of bouncing balls using only a stopwatch, a metre stick and graphical analysis. The experiment emphasizes that simple models, in combination with careful attention to how students make measurements, can lead to good results in a straightforward way.

If a moving stimulus (i.e., launcher) contacts a stationary target that subsequently begins to move, observers attribute motion of the target to the launcher (Michotte, 1946/1963). In experiments reported here, a stationary launcher adjacent to the target appeared or vanished and displacement in memory for the position of the target was measured.…

This article describes technology-based tasks to enhance students' understanding of functions within a framework for thinking about students' development of knowledge.

This descriptive study investigated whether elementary and middle school teachers in the Central Appalachian region were prepared to teach selected standards-based light, force and motion concepts they could reasonably be expected to teach. The study also sought to compare their preparedness for teaching these concepts. (Contains 7 figures and 7…

Commercial computer games contain "physics engine" components, responsible for providing realistic interactions among game objects. The question naturally arises of whether these engines can be used to develop educational materials for high school and university physics education. To answer this question, the author's group recently conducted a…