The aim of this study was to examine the effect of opposition and gender on knee kinematics and ground reaction force during landing from a volleyball block jump. Six female and six male university volleyball players performed two landing tasks: (a) an unopposed and (b) an opposed volleyball block jump and landing. A 12-camera motion analysis…

Mental imagery is thought to share properties with perception. To what extent does the process of imagining a scene share neural circuits and computational mechanisms with actually perceiving the same scene? Here, we investigated whether mental imagery of motion in a particular direction recruits neural circuits tuned to the same direction of…

We present a physically interesting toy, which is easily constructed and operated--the so-called buzzer. In spite of its simplicity, its physical analysis turns out to be rather complex. Thus, it comes as no surprise that most of its users are not familiar with the underlying physical mechanism. In this paper we propose a physical model which…

An analytic approximation of the solution to the differential equation describing the oscillations of a simple pendulum at large angles and with initial velocity is discussed. In the derivation, a sinusoidal approximation has been applied, and an analytic formula for the large-angle period of the simple pendulum is obtained, which also includes…

Recent studies of position-related proprioceptive sense have provided evidence of a nonpreferred left arm advantage in right-handed individuals. The present study sought to determine whether similar asymmetries might exist in "dynamic position" sense. Thirteen healthy, right-handed adults were blindfolded and seated with arms placed on…

Most introductory physics students have seen vehicles with nonstandard wheel diameters; some may themselves drive "low-rider" cars or "big-wheel" pickup trucks. But how does changing wheel diameter affect speedometer readout for a given speed? Deriving the answer can be followed readily by students who have been introduced to rotation, and it…

Teachers usually do not give as much thought to transitions as they do to other facets of the early childhood curriculum. As a result, transitions often lead to chaos and wasted time. But this doesn't have to be the case. If teachers "plan" transitions, as they do other daily components of the curriculum, they can avoid chaos and ensure that…

Making connections is one of the most important foundations involved in learning mathematics. Two projects are presented in this article: one involving Newton's Second Law of Motion and the other involving the determination of star numbers, a type of figurate number. The two invoke seemingly different modalities for students at different levels of…

A core topic in graduate courses in electrodynamics is the description of radiation from an accelerated charge and the associated radiation reaction. However, contemporary papers still express a diversity of views on the question of whether or not a uniformly accelerating charge radiates suggesting that a complete "physical" understanding of the…

National Council of Teachers of Mathematics' (NCTM's) (2000) Connections Standard states that students should "recognize and use connections among mathematical ideas; understand how mathematical ideas interconnect ...; [and] recognize and apply mathematics in contexts outside of mathematics" (p. 354). This article presents an in-depth…

The present experiment examined the effects of acute and daily cocaine on spontaneous behavior patterns of pigeons. After determining the acute effects of a range of doses, 9 pigeons were divided into three groups that received one of three doses of cocaine daily, either 1.0, 3.0, or 10.0 mg/kg cocaine. Measures were taken of spontaneous…

Adults who are blind stood in a room that could be moved around them. A sound source moved with the room, simulating the acoustic consequences of body sway. Body sway was greater when the room moved than when it was stationary, suggesting that sound may have been used to control stance. (Contains 1 figure.)

Memory for objects helps us to determine how we can most effectively and appropriately interact with them. This suggests a tightly coupled interplay between action and background knowledge. Three experiments demonstrate that grasping circumference can be affected by the size of a visual stimulus (Experiment 1), whether that stimulus appears to be…

The experience of controlling one's own actions, and through them events in the outside world, is a pervasive feature of human mental life. Two experiments investigated the relation between this sense of control and the internal processes involved in action selection and cognitive control. Action selection was manipulated by subliminally priming…

The present study examined the effect of perceived motion-in-depth on temporal interval perception. We required subjects to estimate the length of a short empty interval starting from the offset of a first marker and ending with the onset of a second marker. The size of the markers was manipulated so that the subjects perceived a visual object as…