Izvleček
Ta prispevek zaključuje našo serijo štirih člankov o uporabi LED pri poučevanju in učenju fizike. V tem prispevku smo prikazali primere uporabe LED kot črnih skrinjic, ki lahko dijakom pomagajo pri preučevanju mehanskih, električnih, elektromagnetnih in svetlobnih pojavov. Poleg raziskovanja fizike navedenih pojavov LED v tem prispevku pomagajo dijakom povezati raziskave v učilnici z napravami, ki jih uporabljajo vsak dan (žarnice), in z materiali, ki običajno niso povezani s fiziko (kreme za zaščito pred soncem). Poleg lastnosti LED pa smo s tem prispevkom izkoristili tudi prednosti, ki jih ponujajo hitre kamere, to je področje, na katerem naši dijaki postajajo vse bolj spretni in sposobni. Čeprav so LED v tem prispevku uporabljene kot črne skrinjice ali kot kazalniki za preučevanje določenih pojavov, lahko vsakega od eksperimentov uporabljamo tudi za preučevanje fizike LED. Primerjava učinkovitosti LED in žarnic z žarilno nitko se na primer lahko nadaljuje z vprašanji, ki zadevajo mehanizme v ozadju oddajanja svetlobe obeh virov. Pristop črne skrinjice prav tako ponuja možnosti za povezovanje ter iskanje podobnosti in razlik med LED in podobnimi napravami, katerih delovanje temelji na drugačnih fizikalnih principih. Za preučevanje gibanja smo na primer uporabili utripajočo LED iz kolesarske svetilke. Zakaj za enak namen nismo mogli uporabiti utripajoče žarnice na nitko? Kadar dijaki za preučevanje elektromagnetne indukcije uporabljajo LED, se pojavi enako vprašanje, zakaj ne bi uporabili žarnice na nitko? Če povzamemo, LED predstavljajo skriti zaklad za učitelja fizike in zato vas vse vabimo, da raziščete in izkoristite njihove lastnosti, da bi dodatno spodbudili in navdihnili svoje dijake.
Abstract
Light-Emitting Diodes: Solving Complex Problems
This paper concludes our four-item series on using LEDs in teaching and learning physics. Here we showed examples of using LEDs as black boxes that help students study mechanical, electric, electromagnetic, and light phenomena. In addition to exploring the physics of the above phenomena, LEDs in this paper help students connect classroom investigations to the devices they use every day (light bulbs) and to materials that are not commonly associated with physics (sunscreens). In addition to the benefits of LEDs, this paper takes advantage of high-speed video recording, the field where our students are becoming so much more proficient than their teachers. Although in this paper LEDs were used as black boxes or as indicators to investigate particular phenomena, each of the experiments can be used to investigate the physics of LEDs. For example, comparison of the efficiency of LEDs and incandescent light bulbs can continue to the questions concerning the mechanisms behind light emission of both sources. The black box approach also offers opportunities for connections, comparisons, and contrasts of LEDs with other physics devices. For example, we used LED-based blinking bicycle lights to investigate motion. Why couldn’t we use a blinking incandescent light bulb for the same purpose? When the students use the LED to study electromagnetic induction, the same question arises—why not use a light bulb? To summarize, the LEDs are a hidden treasure for a physics teacher and we invite all of you to explore and utilize their properties to inspire your students.