Editorial for the Special Issue “Relativistic Astrophysics”

Relativistic Astrophysics is the branch of astrophysics that studies astronomical phenomena and celestial bodies, for which classical mechanics and Newton’s law of gravitation are inapplicable to creation of suitable models and we have to generalize these approaches following general relativistic prescriptions [...]

Development of Web-Based Physics E-Module Using Discovery-based Learning Model on Newton's Law Materials

The COVID-19 pandemic has led to online learning. The sudden learning process shift from offline to online causes new problems, including students’ difficulty in interacting during the learning process. The media used are usually only in the form of WhatsApp groups and emails which caused students to have difficulty understanding the lesson, limited learning resources and insufficient study time. One way to overcome this problem is to create a web-based physics e-module as an appropriate learning medium in this online learning period. The learning model used was discovery-based learning in order that students could find concepts independently. Therefore, this study aimed to develop a web-based e-module using a discovery-based learning model to increase student's interest and desire to learn. The development used in this research was 4-D (Define, Design, Develop, Disseminate). This research was carried out until the development stage. At the development stage, the e-module validation was carried out by 4 experts as validators. The validation results obtained were 87.8% with very valid criteria. Meanwhile, the practicality of this web-based physics e-module was carried out on students and physics teachers of class XI MIPA 1 SMA N 2 Padang Panjang with percentages of 89.6%, respectively, with very practical criteria. To sum up, this web-based physics e-module using a discovery learning model on Newton's Law material was very valid and very practical to use.

Evaluation of the use of the Moodle Platform for Fundamental Physics Lectures at University

Almost all countries in the world use E-Learning as a teaching medium. Moodle is a Learning Management System (LMS), a free, open-source platform designed to assist educators in creating online courses with dynamic interaction opportunities. In this study, an evaluation of the use of Moodle was carried out, especially in fundamental physics courses (Newton's Law). Evaluation is given by distributing online questionnaires using Google Forms as a database to store answers, collect feedback, and as statistical software to provide analysis of the effect of using Moodle according to students' opinions or perspectives. The study results show that students experience problems in taking tests/quizzes using SEB due to the instability of the internet signal. One of the reasons is that students also have to join the exam zoom simultaneously. Meanwhile, the Newton's Law material provided is very contextual and rich in sample questions, including providing student feedback which is considered good.

Newton’s law of cooling experiment set using Arduino temperature sensor

The research aims to develop the experimental set of the temperature measurement in liquid by Arduino program displaying data on a smartphone via the Blynk application. The experimental set is composed of 1) 2 liquid temperature sensors (DS18B20 model), 2) Arduino program, and 3) LED screen for showing the temperature value in unit of °C and connect to a smartphone. The Arduino temperature sensor 1 and sensor 2 of the experimental set have 0.57% and 0.51% errors, respectively, compared with the temperature sensor of the B Smart Science Co., Ltd. company. The instrument is applied to the physics laboratory on Newton’s law of cooling to find the cooling rate of water and coffee. This low-cost instrument revealed high accuracy results and easy to connect with other devices.

Student Resource on Newton’s Law Concepts Reviewing from Gender: Identification Using Open-Ended Questions

This article aims to find out the resources activated by students in solving Newton’s laws in terms of gender. This research is a quantitative descriptive study with two open test instruments. This research was conducted on 10th-grade students at SMK N 1 Muaro Jambi with 11 female students and 11 male students. The facts obtained in this study indicate that students’ thinking about Newton’s law is still lacking during the learning process. Based on the analysis results of the level of understanding of student concepts, female students understand better than male students. Overall, students fail to summon relevant knowledge when facing problems in the form of phenomena. In addition, they failed to use the knowledge they gained to answer questions. Students’ abilities are activated when they understand a phenomenon influenced by students’ original ideas from their personal experiences.

Analysing an Optimal Angle in Basketball Free Throw

Basketball is a sport, played worldwide by people of all ages, from young to old. The most important skill that a football player should have is shooting. Shooting the ball into the hoop involves projectile motion. The ability of a player to shoot will determine the scores of his/her team. The angle and initial velocity taken during the shooting, plays a vital role, so that a perfect shooting could be achieved. This work has been conducted to determine the optimal throwing angle and initial velocity that a player should take in order to get the best shooting. The relationship of these factors were investigated: the throwing angle and player’s height, initial velocity with the player’s height, as well as the throwing angles versus time taken for the ball to reach the hoop. Our focus is to maximize the height of the ball, before it is thrown. Newton’s law and the concept of projectile motion were applied using a calculus-based model. Relationship between the player’s height with the initial velocity, optimal throwing angle and time taken for the ball to reach the hoop were discussed. Perfect optimal release angle were determined for thirty data of NBA players. It shows that the player’s height is inversely proportional to the initial velocity and the optimal throwing angle. The obtained results also concluded that the optimal throwing angle is directly proportional to the time taken for a ball to reach its maximum height.

Analisis Pemahaman Konsep, Multirepresentasi, dan Kosistensi Jawaban Siswa SMA pada Konsep Hukum III Newton

Newton's third law is a fundamental concept of Physics that is still not reached by students. The tendency of students who do not understand the concept well can be observed by measuring the ability of multi-representation and solutions when solving Physics problems. Therefore, this study aims to determine the concept of Newton's third law understood by students, the multi-representation students have, and the consistency of students' answers in answering physics questions. The participants numbered 28 students from the second semester of high school, selected using the purposive sampling technique, who had just completed discussions about Newton's Law and were willing to participate in this study. Participants were given 6 two-tier question items that managed the R-FCI questions. The results of the answers were analyzed quantitatively to determine the initial percentage description and then analyzed qualitatively to determine understanding, multi-representation ability, and consistency in depth. Most of the participants had low conceptual understanding and answered the questions consistent-wrong. However, based on the analysis of the answer choices and the reasons given, most students understand the meaning of the representation of the answers given

Problem Based Learning on Newton's Law: Can It Improve Student Creativity?

Creativity is important in facing a challenging future life. Therefore, current learning is focused on not only values but also soft skills such as student creativity. Few teachers provide opportunities for students to develop their creativity in the classroom. This creativity can be developed and trained through various learning strategies. Probem-based learning was chosen in this study as a means to increase students' creativity through two learning methods, experiment and demonstration. This study seeks to determine the effect of experimental and demonstration methods with problem-based learning model on student creativity on Newton's law material. The subjects included 72 tenth-grade science students in Surakarta, Central Java. They were selected using the purposed random sampling technique where out of 8 tenth-grade science students in SMA Al Islam, Surakarta, 2 classes that met the research category were selected. This experimental study collected the data using pretest and posttest for cognitive data and questionnaire using a Likert scale for student creativity data. Data were analyzed descriptively through independent sample t-test. The results showed that both methods through problem-based learning model had a significant effect on the level of student creativity. From the characteristics of the methods and the number of students in the high creativity category, experimental method is superior to be applied. It is implied that teachers can use the experimental method with problem-based learning model in Newton's law to develop student creativity soft skills.

Determination of Object Temperature Influenced by Ambient Temperature as a Solution of Newton’s Law of Cooling or Heating Rates

Thermal physics experiments often require accurate data about the thermal condition of the observed object so that its temperature should be measured. The object temperature, which is observed directly using a measuring instrument, does not represent its actual thermal condition because there is an influence of the object temperature and the ambient temperature differences, especially if the object is not in adiabatic isolation. Newton’s Law on cooling or heating rate is used to determine the actual object temperature if the ambient influence is eliminated. The method used in this research is matching analyses between mathematical solutions and empirical data. In thermal physics experiments in laboratories, particularly in the Basic Physics Laboratory, the influence of ambient temperature-known as Newton Correction-often uses a linear temperature-change approach to time. Thus, an analysis of the differential equation model of Newton’s Law of cooling and heating rates is carried out. The result shows that the objects temperature function over time is in the form of an exponential function, both for a constant ambient temperature, and an ambient temperature that changes over time. The result of this analysis is also in line with the experimental data of the Mechanical Heat Equivalence experiment conducted in the Basic Physics Laboratory of Bandung State Polytechnic.