Perhaps the most commonly cited student idea about forces in the literature is the notion of an impetus force, defined as the "belief that there is a force inside a moving object that keeps it going and causes it to have some speed," that can then "fade away as the object moves along." According to the literature, even after…

Background: Roberton's movement components are used to assess fundamental motor skills as segmental developmental sequences. In 1991, Haywood, Williams and VanSant determined that original developmental sequences proposed for the backswing levels of the overarm throw did not encompass all ages. Their study of older throwers identified two new…

Background: The purpose of this study was to examine the effect of the follow-through on thrown ball velocity, potentially justifying inclusion of the follow-through in Roberton's five critical components. Method: Seventy-eight University students participated in the overarm, dominant hand, throwing task, which involved throwing a standard tennis…

An a-posteriori multicentre reliability study was conducted to compare the reliability and magnitude of the maximum power (P[subscript max]) and optimal velocity (V[subscript opt]) between the force-power-velocity relationships during the leg cycle-ergometer and bench press throw exercises. The force-power-velocity relationships were determined in…

Among the student ideas about forces discussed in the literature, perhaps the most commonly reported is the notion of an impetus force, or the "belief that there is a force inside a moving object that keeps it going and causes it to have some speed." For example, Clement asked university students taking introductory mechanics to draw a…

Those who have taught motor skills would most likely agree that the overhand throw may be the most difficult skill for students to master and for instructors or coaches to teach. The timing involved when generating power to performing the overhand throw begins in the toes/feet and moves up the leg, hip, thorax (core muscles), arm, and ends in the…

Kinematic models are often very useful. The back and forth throw of a ball between two ice skaters may help us appreciate the meson exchange theory of Yukawa. If the skaters throw the balls at each other, they move backward, which is equivalent to a repulsive force between them. On the other hand, if they snatch the ball from each other, the…

Background: To improve student performance, teachers need to evaluate the developmental level of the child and to deliver feedback statements that correspond with the student's ability to process the information delivered. Therefore, feedback aligned with the developmental level of the child (aligned developmental feedback--ADF) is sometimes…

The focus of this article is on home visiting in child welfare, an activity which involves a publicly accountable performance of professional tasks in a private space. We specifically examine a recording of a visit by a home learning worker to a mother and her three-year-old child with special needs. In the first part of the article, sequential…

A basketball player attempting a free throw has two parameters under his or her control: the angle of elevation and the force with which the ball is thrown. We compute upper and lower bounds for the initial velocity for suitable values of the angle of elevation, generating a subset of the configuration space of all successful free throws. A…

Researchers are becoming increasingly aware of the advantages of using multiple regression as opposed to analysis of variance (ANOVA) or analysis of covariance (ANCOVA). Multiple regression is more versatile and does not force the researcher to throw away variance by categorizing intervally scaled data. Polynomial regression analysis offers the…

This report, the first of three on the effects of teaching kindergarten children the overhand throw, compares the children's final ball velocities to those of two control groups. Later reports will discuss the effect of instruction on the children's movement processes and the relationship between velocity and movement process. Forty-five children…

Every weekday, millions of American schoolchildren throw away their half-eaten cafeteria lunches so that they can run outside to play. The traditional placement of lunch before recess, coupled with the recent decline in overall recess time to meet academic time constraints, forces children to choose between two essential needs: (1) food; and (2)…

Noddings's radical choice for a particular stance in life is both what makes "Happiness and Education" a thought-provoking book and what also leads me to have some reservations. First, I briefly outline some of these reservations and focus on what I think are two important difficulties "Happiness and Education" faces:…

The equations of motion for electromechanical systems are traced back to the fundamental Lagrangian of particles and electromagnetic fields, via the Darwin Lagrangian. When dissipative forces can be neglected the systems are conservative and one can study them in a Hamiltonian formalism. The central concepts of generalized capacitance and…