摘要：[Five-Tier Diagnostic Test Instrument in Straight Motion Concepts: Development, Validity and Reliability Test and the Limited Trials] Physics lesson is difficult for high school students to understand, including the Straight Motion Concepts. For example, students assumed a pen that was dropped on the floor is an example of free fall motion. According to Physics concept, in free fall motion, a moving object is only affected by the grafity force and the object is in unbalanced condition. Meanwhile, when a pen was dropped, the force that affects not only the gravitational force, but also the force from the student's hand. The mismatch between students' assumptions and the Physics concept shows that students experience what is called a misconception. Such misconception is important to identify using a conception diagnostic test, so that misconception is immediately corrected. Unfortunately, standardized conception diagnostic tests is not yet available. This paper is intended to report the development of a five-tier conception diagnostic test for Straight Motion material, to test its validity and reliability as well as a limited trial to a number of students. 13 valid and reliable questions were obtained so that they were ready to be tested. The internal validity test obtained 94% (valid). The external validity consists of content and construct empirical aspects. The content aspect was valid because the false positive (FP) and false negative (FN) values are 3.27% dan 8.22%. The construct empirical aspect was determined based on the Pearson product moment, the reliability by the Alpha Cronbarch with rtable=0.388 (5% significance level), rxy=0.549 and r11=0.747. The limited trials suggested that most students experienced lack of knowledge.
