Ratchapak Chitaree

Development and Use of a Conceptual Survey in Introductory Quantum Physics

Conceptual surveys have become increasingly popular at many levels to probe various aspects of science education research such as measuring student understanding of basic concepts and assessing the effectiveness of pedagogical material. The aim of this study was to construct a valid and reliable multiple‐choice conceptual survey to investigate students’ understanding of introductory quantum physics concepts. We examined course syllabi to establish content coverage, consulted with experts to extract fundamental content areas, and trialled open‐ended questions to determine how the selected content areas align with students’ difficulties. The questions were generated and trialled with different groups of students. Each version of the survey was critiqued by a group of discipline and teaching experts to establish its validity. The survey was administered to 312 students at the University of Sydney. Using the data from this sample, we performed five statistical tests (item difficulty index, item discrimination index, item point biserial coefficient, KR‐21 reliability test, and Ferguson’s delta) to evaluate the test’s reliability and discriminatory power. The result indicates that our survey is a reliable test. This study also provided data from which preliminary findings were drawn on students’ understandings of introductory quantum physics concepts. The main point is that questions which require an understanding of the standard interpretations of quantum physics are more challenging for students than those grouped as non‐interpretative. The division of conceptual questions into interpretive and non‐interpretive needs further exploration.

The Effect of Interactive Lecture Demonstrations on Students' Understanding of Heat and Temperature: A Study from Thailand.

The purpose of this study was to investigate the effectiveness of Interactive Lecture Demonstrations over traditional instruction on university students’ understanding of heat and temperature. The participants were 327 first year undergraduate students from two science classes in two academic years from the same university in Thailand. One class was the experimental group taught using Interactive Lecture Demonstrations, while the other was the control group taught using traditional instructional methods. The Heat and Temperature Conceptual Evaluation test was administered to the experimental and control groups before and after instruction to evaluate student understanding. We found that the average normalized gain in the experimental group ( = 0.25) was higher than in the control group ( = 0.08). The results indicate that students taught using Interactive Lecture Demonstrations had a better understanding of heat and temperature concepts than students taught using traditional instruction.

Studying the Frictional Force Directions via Bristles.

We present simple apparatus designed to help Thai high school students visualize the directions of frictional forces. Bristles of toothbrushes, paintbrushes and scrubbing brushes are used to demonstrate the frictional forces acting in a variety of situations. These demonstrations, when followed by discussion of free-body diagrams, were found to be effective in teaching frictional force directions.

Polarizing triangular cyclic interferometer for characterizing optical samples with birefringent properties

This paper presents the polarizing triangular cyclic interferometer (pTCi) for characterizing optical samples with birefringent properties such as half- and quarter-wave plates. The interferometric system was set up to analyze the phase retardation of wave retarders in both qualitative and quantitative aspects. For the qualitative aspect, the distinct signal outputs from the inspected birefringent components oriented at particular angles are employed to distinguish different types of optical devices. For the quantitative aspect, the same arrangement could determine the phase difference γ of unknown retarders, so that it could be used to characterize types of samples. The experimental results showed the corresponding results obtained from both mentioned aspects where γ were measured to be 89.62° and 177.17° for half- and quarter-wave plates, respectively. The pTCi has been proved to be a proper scheme to characterize optical samples with birefringent properties.

DEVELOPMENT OF STEFAN-BOLTZMANN BOARD GAME BASED ON GAME CHARACTERISTICS

The purposes of this study are to develop Stefan-Boltzmann board game and evaluate the components (main board, metal hexagon, self-card, information card, and action card) based on five game characteristics which are competition and goals, strategy and tactical, challenges, rules, and fantasy elements. The topics covered by this board game are Stefan-Boltzmann‟s law, radiation power emitted by object, absolute temperature, area, and emissivity. The game characteristics of the board game were assessed by a Physics lecturer and a game expert via a set of 5-point Likert scale assessment tool during the implementation of the board game. The participants were four Indonesian students who had a bachelor degree from faculty of Education and were taking a one year course for the professional physics teacher certification. The score of „main board‟ for each game characteristics are 3.5, 3.5, 4, 5, and 4.5 respectively to competition and goals, game choices, challenges, rules, and game fantasy. In addition, a semi-structured interview was used to collect students‟ opinion on game characteristics that will be used to improve the board game in the future.

Measurement of phase retardation in a liquid crystal variable wave retarder using a polarizing triangular interferometer

The purpose of this study aims to investigate a new method for measuring the phase retardation caused by the induced birefringence from a liquid crystal sample. The method uses a polarizing triangular interferometer whose arrangement requires just a few optical devices. The liquid crystal phase retarder under investigation is inserted into an optical path of the triangular interferometer. The modified interference beam, therefore, is used to characterize the sample property. The method is proved to be effective and suitable for the measurements of polarization related parameters of the optical devices.

The period sensitivity and modal sensitivity of optical fiber force sensor based on mechanical induced ultra-long period fiber grating

In this study, a mechanical induced ultra-long period fiber grating (MULPFG) with periods of several millimeter is demonstrated. The periodic grooved plate used to create the grating in the single-mode fiber (SM600) is the rectangular grooved plate which is fabricated by the 3D printer. The experimental results clearly show that the MULPFGs with the longer grating period are more sensitive to the perturbation force than the shorter grating period. The force sensitivity to the resonance wavelengths of the MULPFG with higher modes are more sensitive than the lower modes. The fabricated force sensor based on MULPFG by using the 3D printer is robust and stable in operation and exhibits a high-sensitivity of ∼ 0.470 nm/N. It offers the advantages of being inexpensive, erasable, and reconfigurable as well.

A demonstration of the simple optical fiber filter in visible and near-infrared wavelengths from green laser and red laser pointers

The optical fiber filter can be used to reject the noise or unwanted spectrum in the optical communication system. In this study, the performance of the optical fiber filter in visible and near-infrared wavelengths is studied. The working principle of the filter is based on the cladding mode coupling to the high order mode introduced by perturbation on a short section of single-mode (SM) fiber with a specific cut-off wavelength. In the previous study, the filtered wavelengths from the SM-fibers with the cut-off wavelength of 600 nm are 547 nm and near IR range (980-1,100 nm). The filtered wavelength from the SM-fiber with the cut-off wavelength of 800 nm is 666 nm. Also, the magnitude of the filtered wavelengths can be controlled by the magnitude of the applied perturbation force. In this study, the green solid state laser with the wavelength of 532 nm (2nd harmonic component), 808 nm (pump wavelength), and 1,064 nm (fundamental component) and the red diode laser with the wavelength of 668 nm are launched into the SM-fiber with the cut-off wavelength of 600 and 800 nm, respectively. The experimental results clearly show that the harmonic wavelength of 1,064 nm of green laser can be filtered out by the fiber with cut-off wavelength of 600 nm up to 66% with the perturbation force 60 N. The fiber with cut-off wavelength of 800 nm can reject the red laser spectrum up to 50% with the perturbation force 80 N.

A low-cost demonstration kit for locating an image formed by a plane mirror integrated with a ray diagram

This article introduces a low-cost, easy to make apparatus that can be used to locate the position of an image formed by a plane mirror. The apparatus is combined with a method used to identify an image’s position by drawing a ray diagram, based on the principle of reflection, to show how an image is formed. An image’s distance and an object’s distance can be measured precisely. In addition, the size of an object and an image can be determined accurately.

The use of a bristle tips model in teaching dynamic friction

We present a bristle tips apparatus devised to help students visualize frictional force directions in dynamic situations simply.