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This study investigated the academic achievement of students at the end of the school year in knowledge of gravity, acceleration, and the relationship between distance, time, and speed. The students' teachers were in the Cheche Konnen professional development seminar for three years. Participating grade levels included a heterogeneous, combined 1st/2nd grade elementary classroom, a combined 5th/6th grade Haitian Creole bilingual classroom, and a heterogeneous 7th grade science class. (Contains 10 references.) (YDS)

This paper reports on the results of substituting one-hour active-engagement tutorials using microcomputer based laboratory (MBL) equipment for traditional problem-solving recitations in introductory calculus-based mechanics classes for engineering students at the University of Maryland. The results of two specific tutorials--one on the concept of instantaneous velocity and one on Newton's third law--were probed using standard multiple choice questions and a free-response final exam question. Findings indicate that the MBL tutorials resulted in a significant improvement compared to the traditional recitations when measured by carefully designed multiple-choice questions. Results of the free-response item indicate that although the tutorial students did somewhat better in recognizing and applying the concepts, improvement is still needed. (Contains 21 references.) (Author/WRM)

The angular momentum of a human body derived from both the angular velocity and angular displacement, utilizing cinematographic records has not been adequately assessed, prior to this study. Miller (1970) obtained the angular momentum but only during the airborne phase of activity. The method used by Ramey (1973) involved a force platform, but also had its limitations because it had restricted use to only force platform activities. The mass of segment, the transverse moment of intertia of segment, the angular velocity of segment i about its transverse axis, the projected distance between the c.g. of segment i and the c.g. of the whole body, and the angular velocity of the c.g. of segment i about the c.g. of the whole body, were used in this study to develop a formula to represent the angular momentum of a multi-segment body about one of its axes. Results indicated that the method used in this study yields an acceptable first approximation of the angular momentum of a human body in motion. This method can be used for numerous tests of different physical activities. (Cinematographic diagrams are included.) (MK)

Television wide-angle lenses expand distances and increase apparent velocity, while long lenses compress space and reduce apparent velocity. Based on these assumptions, a study was conducted (1) to examine the ability of viewers of different ages to recognize how lenses change the "real world" they project and (2) to extend Jean Piaget's research on cognitive development to television. Subjects were 46 third grade students, 47 seventh grade students, and 54 undergraduate college students. These grade levels were chosen to represent individuals in the concrete operational stages, in transition from concrete to formal operational stages, and in the formal operational stages as identified by Piaget. The subjects were asked to judge velocity and distance in three conditions in which images photographed by lenses of different focal lengths were compared. In addition, the subjects completed tests to measure their experience with television. The results suggest that the focal length of a television camera lens influences how a large percentage of viewers perceive velocity and distance in televised events. The results also confirm a progression in cognitive development from concrete operational thought to formal operational thought as discussed by Piaget. (FL)

Discussed are data concerning a simple visuomotor tracking task, especially the expectations and cognitive representations involved in performing such a task. The task consisted in tracking the horizontal displacement of a target spot on the screen by appropriate forearm rotations. Each subject participated in two sessions: first, at a .8 Hz target frequency and, at least 48 hours later, at a .2 Hz target frequency. In all cases, the performances were recorded during 35 full cycles of target movement. Subjects were 50 children 5 through 9 years of age. Results indicated the existence of a 90 degree phase lag at .8 Hz for the younger groups which, with increasing age, approaches monotonically the adult performance. Two control experiments, exploring the role of the velocity of the stimulus on performance, further investigated the basic characteristics of performance at the age of 6. It is concluded that the tracking of sinewaves by children depends dramatically on target frequency. The acquisition of this skill cannot be adequately described as a monotonic maturational process. One major modification appears at the age of 6 years in the strategy of perceptuo-motor coordination. This modification is relative to the control of the velocity of the movement only in case of spatio-temporal constraints. Two tables and five figures are appended. (RH)

This study investigated how preadolescents and adolescents solve problems involving three temporal dimensions. Specifically examined was the question of whether speed and space information would influence the time judgments of 90 subjects 9, 12, and 15 years of age who solved 16 word problems describing the displacements of two cars. The problems included either relative orders of succession or included one order of succession and the relative duration of the events. Each problem was presented twice: once with speed information and once wih space information. Participants deduced either the relative duration, or the relative beginning or ending times of the events. Duration judgments and order of succession judgments were compared. Findings indicated that older children made more correct judgments than younger children. As predicted, certain problems were facilitated when presented with speed information and were more difficult when presented with space information. The effect was reversed for the other problems. Participants had more difficulty reconstructing the beginning time of an event than deducing the ending time. Results support the notion that specific relations exist between the concepts of time, speed, and space. Time judgments may be hindered if these relations conflict. (RH)

Describes a study designed to identify the various reasoning procedures used by students (n=229) in comparing the average velocities of two moving bodies; compare the differences among the procedures used by students at different school levels; and analyze the relationship between automatic and human diagnoses to identify diagnostic errors of the automatic system. (ZWH)

Presents a case study of how one 11th-grader learned the meaning of the velocity sign. Her learning was not just an acknowledgment of a rule but also a broad questioning and revision of her thinking about graphs and motion. (16 references) (Author/MKR)

Examines the influence of two factors of the process of graphing on rural students' (n=93) ability to comprehend kinematics graphs on constant velocity events. Students exhibited difficulty in constructing and comprehending graphs of derived variables and were unaware of their own graphing skills deficiencies. (34 references) (MDH)

A model for solution of the motion correspondence problem is presented that is capable of maintaining the identities of individuated elements as they move. Many properties of the model are consistent with what is known about physiological mechanisms underlying human motion perception. (SLD)