Could Physics Teachers Also Have Misconceptions on Basic Kinematics?

The role of a physics teacher in learning is to facilitate student activities to construct correct conceptual understanding as that of a scientist. As the primary source of knowledge for students, a physics teacher is required to have the right concept, but this demand is not necessarily fully fulfilled. This study aims to determine the profile of physics teachers’ understanding of concepts on kinematics material detected by a four-tier misconception test. Participants in this study were 20 high school physics teachers in Surabaya. Based on the results of data analysis, it was found that the dominant misconceptions included: (1) Two objects that make the same displacement at the same time interval will have the same velocity, regardless of the type of movement of the two objects (2) Objects that move vertically straight up or down will always have the acceleration of motion equal to the acceleration of gravity which is directed downwards. (3) As long as the object’s position is at positive coordinates, it means the object is moving in the forward direction. (4) The graph of velocity against time, which has a positive gradient, means that the object always moves forward (5) In parabolic motion, the length of time an object is in the air only depends on the length of its path, the longest path will require the longest time. (6) In parabolic motion, the final speed of an object when it lands on the ground depends not only on its initial speed but also on its elevation angle. The findings of several misconceptions above show that even a physics teacher cannot escape misconceptions. Therefore, it is crucial for a teacher to be able to remedy the misconceptions he suffers so that these misconceptions are not transmitted to the students he teaches. This finding is the first step for researchers to detect misconceptions, followed by the application of certain learning methods to remedy misconceptions in future research.


Introduction
The main goal of constructivist learning is to facilitate student activity to construct correct conceptual understanding as that of a scientist.Conceptual understanding is the primary key to achieving a higher cognitive level of analysis, evaluation, and creation [1,2].Understanding the concepts in learning physics is the main goal, but students still experience a lot of confusion with the concepts being taught.Increasing students' understanding of scientific concepts and attitudes is a goal to be achieved in the learning process [3].However, the reality of many studies reveals that many students still experience misconceptions about physics concepts [4] and even many prospective teachers experience misconceptions [5][6][7].
Misconceptions are misunderstandings in connecting a concept with other concepts, between new and old concepts that already exist in students' minds, so the wrong concept is formed.The student's conception is different or contradicts the scientist's conception.There are five misconceptions: presumption, non-scientific beliefs, conceptual misunderstandings, regional language misconceptions (vernacular misconceptions); and factual misconceptions.There are four causes of misconceptions: students, teachers, teaching materials or literature, context and teaching methods [8].
Misconceptions originating from students can be grouped in several ways: prior knowledge or prejudice, associative thinking, humanistic thinking, incomplete or wrong reasoning, wrong intuition, stages of student cognitive development, student abilities, and student interests [9].Teachers who do not master the material or understand physics material incorrectly will cause students to experience misconceptions.Some physics teachers do not understand the concept of physics well, so this misunderstanding is passed on to students [10].Teaching materials or literature are an integral part of learning and curriculum, especially physics, and play a very important role in shaping the learning of physics as it is today.Teachers and students are never separated from textbooks and literature in the learning process.Textbooks used as teachers' only source of guidance will encourage misconceptions among teachers [11].Several learning methods teachers use, especially those that emphasize only one aspect of the concept of the material being worked on, although they help students understand the material being taught, often have a negative impact, causing student misconceptions.
The teacher as a source of misconceptions for students must get the main attention, because the teacher who is supposed to remedy student misconceptions will transmit his misconceptions when he experiences misconceptions.Therefore, it is necessary to do a misconception detection test first to determine whether a teacher has a misconception.Previous research discussing kinematics misconceptions in students has been widely carried out [12][13][14][15] and also on prospective teachers [16,17] but rarely has research been conducted on active teachers [18].This research was conducted to determine the profile of physics teacher's understanding of concepts on kinematics.There are many kinds of misconception detection tests but the most effective test according to a literature review conducted by Rebiantoro [19] is the four-tier misconception test.In this research, a four-tier misconception kinematic test was conducted to determine the profile of physics teacher's understanding of concepts on kinematics.

Method
This research is exploratory descriptive research.The sample of this research was 20 senior high school physics teachers in Surabaya from public and private schools.The teachers were asked to complete a four-tier kinematics misconceptions diagnostic test within the allotted time.The four-tier diagnostic test on kinematic topics developed by modified from the Force Concept Inventory (FCI) developed by Hesthenes [20] and several other sources consists of 20 test items.The teacher's response consists of four parts: (1) the main answers to the questions (2) the level of confidence in the truth of the answers (3) the reasons for the answers given, and (4) the level of confidence in the truth of the reasons given.In this study, researchers used the Certainty of Response Index (CRI) scale of 6 (0-5), with the criteria as shown in Table 1 [21].The teacher's answers were then grouped into four answer categories, namely Understanding of the Concept (U), Partial Understanding (PU), Misconceptions (M), Not Understanding the Concept (NU), and Un-Code (UC) as shown in Table 2. Un-Code (UC) There is "tier" which aren't answered or the answers is more than one available option Analysis of teacher answers was carried out in two ways: based on each question and based on each teacher's answer.The problem-based analysis aims to find out which material misconceptions are generally experienced by teachers.In contrast, the analysis based on each teacher's answers aims to determine the level of misconceptions of the teacher.

Results and Discussion
Based on the analysis of the teacher's answers to the kinematics misconception detection test by grouping according to the combination of the four-tier Diagnostic Test answer categories, the results of the analysis per question were obtained as shown in Table 3.The teacher's response to questions 14, 16 and 15 revealed the three lowest misconceptions.Meanwhile questions that received 25% or more misconceptions occurred in questions number 6, 4, 1, 3, 10, 2, 7, 5, 8, 17, and 19.Suppose we examine more deeply the misconceptions experienced by teachers based on the analysis of the most answers that are wrong and have a high level of confidence.In that case, findings of teacher misconceptions will be obtained as presented in Table 4.

No Sub Chapter
Question number Misconception more than 25 % Misconception Findings (3) Two objects that make the same displacement in the same time interval will have the same velocity, regardless of the type of movement of the two objects (2) The object that takes the more significant displacement per unit time will have the greater acceleration, even though they are both in uniform linear motion.(4) An object that moves vertically up or down will always have the same acceleration as the acceleration due to gravity directed downwards.(10) An object that stops for a moment shows that there is no acceleration on the object.17) In parabolic motion, the length of time an object is in the air only depends on the length of its path.

No Sub Chapter
The longest path will take the longest time.(19) In parabolic motion, the final speed of an object when it lands on the ground depends not only on its initial speed but also on its elevation angle.Based on the misconception findings listed in Table 4, it shows that teachers also experience misconceptions about kinematics in the topics: Linear Motion, Reading Linear Motion Graphs and Parabolic Motion.Students also often encounter these findings of misconceptions of kinematics by teachers, including: speed and acceleration [23,24], parabolic motion [25], and understanding graphs [26].While the analysis of misconceptions based on the answers of each teacher obtained the results as shown in Table 5.Based on Table 3, the general profile of the teacher's understanding of the basic concepts of kinematics can be seen from the percentage of each category, successively from the highest: Partial Understanding (PU) 43%, Misconceptions (M) 25.5%, Understand the Concept (U) 17% and Not Understand the Concept (NU) 14.5%.This shows that the teacher's mastery of kinematics concepts is still very low and still has many misconceptions.It is necessary to learn to strengthen concepts and remediate misconceptions.

Conclusion
The teacher's misconception profile shows that the teacher's conceptual understanding of kinematics is still low and the teacher's misconceptions are still very high.Teachers' misconceptions occur in several sub-chapters: Linear Motion, Reading Linear Motion Graphs, and Parabolic Motion.In more detail, the findings of misconceptions experienced by teachers include: (1) Two objects that make the same displacement at the same time interval will have the same velocity, regardless of the type of movement of the two objects (2) Objects that move vertically straight up or down will always have the acceleration of motion equal to the acceleration of gravity which is directed downwards.(3) As long as the object's position is at positive coordinates, it means the object is moving in the forward direction.(4) The graph of velocity against time, which has a positive gradient, means that the object always moves forward (5) In parabolic motion, the length of time an object is in the air only depends on the length of its path, the longest path will require the longest time.(6) In parabolic motion, the final speed of an object when it lands on the ground depends not only on its initial speed but also on its elevation angle.
Based on the findings of this study, it is necessary to regularly evaluate teachers' mastery of concepts for various physics materials.Evaluation of the mastery of physics concepts can be done at the start of the semester and followed up by learning program for remediation of misconceptions experienced by teachers.This is important to do so that the misconceptions experienced by the teacher are not transmitted to students.
Detecting misconceptions before the learning process is essential to determine the profile of students' conceptual understanding.However, based on the experience of this research, analyzing the four-tier misconception diagnostic test takes quite a long time because it is done manually.As an alternative

Table 1 .
The Certainty of Response Index (CRI) scale and the criteria.

Table 3 .
Misconceptions based on the Four-Tier Diagnostic Test for each question

Table 5 .
Recapitulation of each teacher's conception based on the Four-Tier Diagnostic Test