We study the turning point problem of a spherical pendulum. The special cases of the simple pendulum and the conical pendulum are noted. For simple initial conditions the solution to this problem involves the golden ratio, also called the golden section, or the golden number. This number often appears in mathematics where you least expect it. To…

Four experiments investigated influences of irrelevant action effects on response selection in Simon tasks for which tone pitch was relevant and location irrelevant, and responses were clockwise-counterclockwise wheel rotations. When the wheel controlled left-right movement of a cursor in a direction opposite an instructed left-right hand-movement…

Previous research, in which static figures were used, showed that the ability to perceive illusory contours emerges around 7 months of age. However, recently, evidence has suggested that 2-3-month-old infants are able to perceive illusory contours when motion information is available (Johnson & Mason, 2002; Otsuka & Yamaguchi, 2003). The present…

In this paper, we analyse a number of paradoxical teaching problems of classical electrodynamics, dealing with the relativistic transformation of force for complex macro systems, consisting of a number of subsystems with nonzero relative velocities such as electric circuits that change their shape in the course of time. (Contains 7 figures.)

A number of interesting demonstrations of circular and satellite motion have been described in this journal. This paper presents a variation of a centripetal force apparatus found in G.D. Freier and F.J. Anderson's "A Demonstration Handbook for Physics," which has been modified in order to demonstrate both centripetal force and satellite motion.…

Energy is a critical concept in physics problem-solving, but is often a major source of confusion for students if the presentation is not carefully crafted by the instructor or the textbook. A common approach to problems involving deformable or rotating systems that has been discussed in the literature is to employ the work-kinetic energy theorem…

A well-known classroom demonstration involves the rolling of hollow and solid objects down an incline. The fact that the objects roll at different rates can be used as a starting point in introducing students to rotational dynamics and rotational kinetic energy. In this paper we describe a simple quantitative version of the demonstration that is…

The purpose of this study was to investigate the influence of physical movement on listeners' perception of musical performance. Participants ( N = 112) rated a professional pianist performing with a recorded musical excerpt under three physical movement conditions: "no movement", "head and facial movement" and "full body movement". Relationships…

In the "Third Day" of the "Discourses and Mathematical Demonstrations Concerning Two New Sciences" Galileo Galilei describes the famous experiment of the inclined plane and uses it to bring an experimental confirmation to the laws of uniformly accelerated motion. We describe a reconstruction of the experiment and how the results can be used for…

Purpose: This study compared movement characteristics of markers attached to the jaw, lower lip, tongue blade, and dorsum during production of selected English vowels by normal speakers and speakers with dysarthria due to amyotrophic lateral sclerosis (ALS) or Parkinson disease (PD). The study asked the following questions: (a) Are movement…

The attentional blink refers to the transient impairment in perceiving the 2nd of two targets presented in close temporal proximity in a rapid serial visual presentation (RSVP) stream. The purpose of this study was to examine the effect on human attentional-blink performance of disrupting the function of the magnocellular pathway--a major…

Do 14- to 17-month-olds notice the paths and manners of motion events? English- and Spanish-learning infants were habituated to an animated motion event including a manner (e.g., spinning) and a path (e.g., over). They were then tested on four types of events that changed either the manner, the path, both, or neither component. Both English- and…

While previous research has demonstrated that people's movements can become coordinated during social interaction, little is known about the cognitive consequences of behavioral synchrony. Given intimate links between the systems that regulate perception and action, we hypothesized that the synchronization of movements during a dyadic interaction…

Representations of centrifugal forces are derived in a variety of rotating frames. Although the rotating angle of a point mass relative to an inertial frame is often confused with the rotating angle of a rotating frame relative to the inertial frame, they should be differentiated. (Contains 4 figures and 1 table.)

Ocular pursuit movements allow moving objects to be tracked with a combination of smooth movements and saccades. The principal objective is to maintain smooth eye velocity close to object velocity, thus minimising retinal image motion and maintaining acuity. Saccadic movements serve to realign the image if it falls outside the fovea, the area of…