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Development of concept essential in kinematic topics

Essential concepts were important aspects in physics education, especially in the study of learning development, student evaluation, and curriculum planning. Several types of concept analysis models are commonly applied in the context of physics, i.e. sematic network techniques, concept formation (concept analysis), concept maps, and representing substantive structure. The stages of essential concept development were concept analysis, concept map and essential concept. The research method used development research. The stages of development research included (1) the preliminary study phase, (2) the development study phase, (3) the evaluation phase. The main results of this study were essential concepts on the topic of Kinematics.


Introduction
The concept is specific information about one or several objects, events, or processes; the object is a part or group of certain objects or related to another group of objects [1]. Content analyses (concept analyses) are important aspects in physics education, especially in the study of learning development, student evaluation, and curriculum planning [2]. Several types of concept analysis models are commonly applied in the context of physics, i.e. sematic network technique [3], concept formation (concept analysis) [4], concept maps [5][6][7], and representing substantive structure [8]. The stages of developing essential concepts are concept formation and concept maps.
Analysis of concept is formal strategy for investigating concepts and deciding how the concept was learned. Concept analysis was carried out through seven steps, i.e. (1) determining the name or label of the concept, (2) definitions of concepts, (3) types of concepts, (4) critical attributes, (5) variable attributes, (6) conceptual positions (superordinate, ordinate, subordinate), (7) examples and nonexamples [9].
Concept maps are two-dimensional diagrams, hierarchical diagrams of conceptual relationships described important concepts and propositions in the knowledge domain [10]. Concept maps are schematic instrument for representing a set of concept meanings embedded in the form of propositions [6,8]. The main ideas of Ausubel's cognitive theory are the basis for developing concept maps [11]. Ausubel's assimilation theory explain learning are the activity of assimilating new concepts and propositions into concepts and proportions in students' cognitive [12][13]. The main components of concept map are hierarchy of concepts, relationships between concepts, cross-links, and examples of concepts [8].
Kinematics is a basic concept in physics as a foundation for students to comprehend the concept of physics comprehensively. Kinematics focuses on the motion of objects assuming the environment has  [14][15]. The main concepts of kinematics are translational and rotational motion.
The urgency of developing essential concepts on the topic of kinematics is to make it easier for instructors to know the concept hierarchy comprehensively as a base in developing the learning procedures in the class and determining assessment models that are in accordance with the characteristics of the Kinematics concept. The essential concepts for the topic of Kinematics has not been well developed. Thus, the development of essential concept on the topic of kinematics is considered important to develop.

Methods
This research was a development research adapted Sugiyono's development design model [16]. The procedure of development research included (1) the stage of the preliminary study, (2) the stage of development studies, and (3) the evaluation phase. The preliminary study phase was focused on documentation study activities and literature studies. Documentation studies carried out by analysis of physical textbooks used in lectures. The literature studies explored the characteristics and stages of developing concept analysis, concept maps, and essential concepts in articles and textbooks. The development study phase was carried out product design concept analysis, concept maps, and essential concepts. The stages of developing concept analysis were adapted from Herron [9]. The stages of developing concept maps were adapted from Novak and Gowin [6,8]. The evaluation phase was conducted to validate the results of concept analysis, concept maps, and concept essential that have been developed. Validation was carried out by experts in physics and pedagogy in physics.

Preliminary Study Stage
The documentation studies of several physic textbooks [14,17] on the Kinematics concept focused on discussing motion without the influence of forces acting on motion. The concept of motion included translational motion, rotational motion, one-dimensional motion, and two-dimensional motion. Some examples of physical quantities in translational motion were distance, displacement, instantaneous speed, average speed, instantaneous acceleration, and average acceleration.

Development Stage
The stages of developing concept analysis were (1) determining the name or label of the concept, (2) definitions of concepts, (3) types of concepts, (4) critical attributes and variable attributes, (6) concept positions: superordinate, ordinate, subordinate, (7) examples and non-examples. Types of concepts in concept analysis were (1) the concrete concepts i.e. concepts were example, critical attributes and variable attributes are easily seen clearly; (2) abstract concepts i.e. concepts whose examples cannot be seen; (3) concepts with abstract critical attributes, example can be seen; (4) The concept was based on principle knowledge, i.e. a concept that required knowledge principles to distinguish between examples and non-examples; (5) the concept involved symbol representation. (6) concepts that explained an attribute or atribut. The theoretical attribute stated main characteristics of concept that outlines the concept definition [9]. The concept analysis prototype on the Kinematics topic is shown in Table 1. The stages of developing a concept map were (1) reviewing the topic or concept domain, i.e. reading books or articles, reflecting on the concepts being mastered; (2) identifying the main concepts, i.e. listing some concepts considered important; (3) determine the hierarchy of concepts, i.e. determine the most inclusive concepts to concepts were less inclusive of the main concepts; (4) linking or labeling relationships between concepts, i.e. understanding the whole relationship between concepts in a map; (5) deepening or broadening concept maps, i.e. adding subordinate concepts to the map as much as possible to deepen and broaden knowledge on the concept; (6) making a cross-link, i.e. trying to connect and label the relationship between the concepts that already exist on the map [10,11]. The concept map prototype on the Kinematics topic is shown in Figure 1.  The last stages of development were essential concepts as derivatives from the stages of concept analysis and concept maps. An example of an essential concept prototype on the topic of Kinematics is shown in Table 2. Table 2. The prototypes of essential concepts on the topic of Kinematics

Codes Essential Concepts K1
Distance is the length of the passage through which the particle passes K2 Displacement is a vector quantity stated the change in initial to final potion, and the magnitude is the shortest distance between two positions K3 Average velocity is the particle displacement divided by the time interval of displacement K4 Average speed is the total distance divided by time K5 Instantaneous velocity is the limit of the particle displacement ratio divided by the time interval, with an interval close to zero K6 Instantaneous speed is the magnitude of instantaneous velocity K7 Average acceleration is a change in particle velocity per unit time K8 Average speeding up is the magnitude of the average acceleration Rotational motion is the motion of rigid body on fixed axis with path in the circle form

Evaluation Stage
The results of the development of concept analysis, concept maps, and essential concepts were validated by two experts in the field of physics education. In general, there were some expert suggestions on concept analysis products, concept maps, and essential concepts developed were shown in Table 3. Suggestions from the validator as basis for improving the instruments developed.

Conclusion
The product of this research is essential concepts on the Kinematics topic. The stages of developing essential concept include the preliminary study stage, the development stage, and the evaluation stage. The main function of essential concepts is to make it easier for teachers to comprehensively understand the hierarchy and characteristics of the concept as foundation in developing the learning process in the classroom and determine assessment models that are appropriate with the characteristics of the Kinematics concept.