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Construction and Application of the Telescope in Teaching Physics
Get PDFU prvom dijelu diplomskog rada dan je povijesni pregled razvoja teleskopa. Opisani su
pojedini nedostaci prvih teleskopa refraktora, kao i tadašnje teorije zbog kojih su kromatske aberacije
dugo vremena bile misterija, što je odgađalo izum i razvoj reflektora. Središnji dio rada posvećen je
zakonima geometrijske optike na kojima se temelji princip rada ne samo teleskopa, već i drugih
optičkih instrumenata. Također, navedene su i opisane bitne karakteristike teleskopa. Upute kako
samostalno izraditi jednostavan teleskop dane su u završnom dijelu rada u kojemu su dani i primjeri
kako primijeniti teleskop u nastavi fizike u osnovnim školama i prirodoslovno-matematičkim
gimnazijama.The first part of this thesis includes the historical overview of the development of the
telescopes. Certain disadvantages of first refractors are described, as well as theories for the cause and
misunderstanding of chromatic aberration remained a mystery for a long time that delayed the
invention and development of reflectors. The central part of the thesis deals with the underlying
principle of the telescope and other optical instruments – laws of geometrical optics. Furthermore, the
most important characteristics of telescope are listed and described in more detail later in the thesis.
The final part of the thesis contains instructions that one can use in order to independently construct
a simple telescope. Moreover, examples that are listed show how to apply the telescope in teaching
physics in the primary and secondary schools
Achieving Low Temperatures
Get PDFU ovom završnom radu opisano je nekoliko metoda za postizanje niskih temperatura: hladnjak,
kaskadno hlađenje, Lindeov uređaj, Joule-Thompsonov tip ukapljivača, dilucijski hladnjak te
hlađenje laserom.In this bachelor's thesis is described several methods for achievement low temperatures:
refrigerator, cascade cooling, Linde's device, Joule-Thompson's type liqueur, dilution cooler and
laser cooling
Diagnostic Clinical Applications of Ionizing Radiation
Get PDFTema kojom se bavi ovaj diplomski rad je ionizirajuće zračenje kod dijagnostičkih
medicinskih uređaja. Fizikalnom interpretacijom objašnjeni su temelji zračenja u radiologiji i
radiobiologiji. Dalje kroz rad obrađeni su razni medicinski dijagnostički uređaji, redom: rendgen,
kompjutorizirana tomografija – CT, jednofotonska emisijska kompjutorizirana tomografija –
SPECT, pozitronska emisijska tomografija – PET, denzitometar i mamograf. Izneseni su principi
rada pojedinog uređaja te utjecaj ionizirajućeg zračenja na čovjeka i okolinu.
Rad se zaključuje poglavljem zaštita od zračenja gdje su objašnjeni prevencija i zaštita od
ionizirajućeg zračenja popraćena zakonskom regulativom. Cilj rada je upoznati studente i
profesore s principom rada medicinskih dijagnostičkih uređaja i ukazati na utjecaj ionizirajućeg
zračenja na čovjeka i okolinu.The topic of this graduate thesis is diagnostic clinical applications of ionizing radiation.
Physical interpretation explains the basics of radiation in radiology and radiobiology. Several
medical diagnostic devices have been analyzed, namely: X- Ray, Computerized Tomography –
CT, One-Photon Emission Computerized Tomography – SPECT, Pozitron Emission Tomography
– PET, Densitometer and Mammography. The principles of the work of each device and the
influence of ionizing radiation on humans and the enviroment are laid down.
The paper concludes with the chapter on radiation protection where the prevention and
protection from ionizing radiation is accompained by legal regulation. The aim of the paper is to
introduce students and professors to the principle of the operation of medical diagnostic devices
and to point out the influence of ionizing radiation on humans and the enviroment
The Big Bang Theory
Get PDFVeliki prasak naziv je kojeg je izvorno dodijelio Sir Fred Hoyle, a opisuje standardnu
sliku svemira i kako se on razvija. Trenutno u stanju širenja i hlađenja, svemir je u prošlosti bio
imao veću temperaturu i gustoću. Model Velikog praska prestaje vrijediti na samom početku
prostora i vremena zbog postojanja singularnosti. Stoga je u značajnoj mjeri nepotpun, a takav će
i ostati dok se ne postavi kvantna teorija gravitacije.
Rad je podijeljen na pet glavnih cjelina. U prvoj će cjelini biti opisana kratka povijest
svemira od Velikog praska do sadašnjosti, u drugom dijelu će biti dokazi koji podupiru teoriju
Velikog praska a u trećem dijelu su problemi vezani uz teoriju. U predzadnjoj cjelini spomenute
su neke od ostalih poznatijih teorija postanka svemira, i naposljetku, zadnji dio rada fokusiran je
na budućnost svemira.Big Bang is a term which was originally given by Sir Fred Hoyle, and it describes
standard image of the universe and how the universe expands. Currently in a state of expanding
and cooling, universe was much hotter and denser in the past. The Big Bang model cease to be
valid at the very beginning of space and time because of the existence of singularity. Therefore,
the theory is significantly incomplete, and it will remain incomplete until a quantum theory of
gravity is achieved.
The work is divided into 5 main parts. In the first part, the brief history of the universe
from the Big Bang till present time will be explained. In the second segment there will be proofs
that support the theory, and in the third segment there will be problems regarding the theory. In
the fourth part, some of the more famous theories on the origin of the universe will be
mentioned. And, ultimately, the last part of the work will be focused on the future of the
universe
The Cosmic Microwave Radiation
Get PDFMikrovalno kozmičko zračenje je zračenje koje ispunjava svemir, padajući na Zemlju iz
svakog smjera skoro jedinstvenom gustoćom. Od ranog 20. stoljeća, dva koncepta
transformirala su način razmišljanja astronoma o promatranju svemira. U sklopu prvog
koncepta, svemir je fantastično velik - dio svemira vidljivog danas je sfera radijusa približnih
15 milijardi svjetlosnih godina, i mi vjerujemo da je to samo vrh ledenjaka. Drugi koncept je
da svjetlost putuje ustaljenom brzinom. Jednostavna posljedica ovih ideja je da se gledanjem
u udaljenije predmete vidi sve dalje i dalje u prošlost.The cosmic microwave background radiation is a radiation that fills the universe, falling on
Earth from every direction with nearly uniform intensity. Since early twentieth century, two
concepts have transformed the way astronomers think about observing the universe. The first
is that it is fantastically large; the portion of the universe visible today is a sphere nearly 15
billion light-years in radius, and that, we believe, is just the tip of the iceberg. The second is
that light travels at a fixed speed. A simple consequence of these ideas is that as you look at
more and more distant objects, you see farther and farther back in time
Thermionic emission
Get PDFU ovom završnom radu opisana je pojava termoelektronske emisije. Osim same
termoelektronske emisije ovaj rad sadrži teme koje nam pomažu shvatiti tu pojavu. Ukratko
govoreći, termoelektronska emisija je pojava kada slobodni elektroni zagrijavanjem dobivaju
dovoljnu energiju za napuštanje metala. Na kraju rada sam navela primjenu termoelektronske
emisije i zašto je ona tehnički najvažnija emisija.This bachelor's thesis describes the phenomenon of thermoelectric emission. Apart from the
thermoelectric emission itself, this paper contains topics that help us understand this
phenomenon. Briefly, a thermoelectric emission is a phenomenon when free electrons get
enough energy to leave the heated metal. At the end of my work, I came up with the use of
thermoelectric emissions and why it is technically the most important emission
Becquerel Experiment
Get PDFU diplomskom radu rekonstruiran je eksperiment kojim je otkriveno radioaktivno zračenje. Rad
se sastoji od dva dijela. U prvom, teorijskom dijelu, opisan je život i otkriće Antoina Henria
Becquerela te vrste i izvori radioaktivnog zračenja. Nakon fizikalnog dijela, slijedi kratak uvod u
osnove fotografije s prikazom procesa razvijanja fotografskog filma. U eksperimentalnom dijelu,
rekonstruiran je Becquerelov eksperiment korištenjem dva minerala (uraninit i zippeit) te su
prikazani rezultati dobiveni ozračivanjem fotografskog filma.In this Bachelor thesis, the reconstruction of Becquerel’s experiment which led to discovery of
radioactivity is presented. It is devided into two main parts: in first, the theoretical part, the life
and discovery of Antonie Henri Becquerel is described as well as types and sources of
radioactivity. Afterwards, the short introduction to photography, with process of chemical
treatment of a photographic film is presented. In the experimental part, the reconstruction of the
Becqurel’s experiment, with using two minerals (uraninite and zippeite) was preformed and the
results of irradiation of photographic films are presented
Elektromagnetic Oscillations
Get PDFU ovom diplomskom radu naglasak je na upoznavanju elektromagnetskih pojava vezanih za
titranje, odnosno elektromagnetske titrajne sustave čija je primjena u današnjoj tehnologiji vrlo
široka. U prvom dijelu dane su osnove titranja, odnosno mehaničkog titranja, kao i najvažnije
relacije koje opisuju takve titrajne sustave, posebice harmonijska titranja. Drugi dio donosi
neophodni uvod u elektromagnetske pojave i najvažnije osobine magnetskih i električnih pojava,
dok treći dio pokazuje na koji se način mogu primijeniti mehanički titrajni sustavi i analogno njima
(krenuvši od Maxwellovih jednadžbi) opisati elektromagnetski titrajni sustavi koristeći, između
ostalog, neke od koncepta navedenih u prvome dijelu rada.In this graduate thesis, the emphasis is on introducing electromagnetic phenomena related to
oscillation, ie electromagnetic oscillation systems, whose application in today's technology is very
wide. In the first part, the basics of oscillation or mechanical oscillation are given as well as the
most important relationships that describe such oscillating systems, especially harmonic
oscillation. The second part introduces the necessary introduction to electromagnetic phenomena
and the most important characteristics of magnetic and electrical phenomena, while the third part
shows how mechanical oscillation systems can be applied and analogously (starting with Maxwell
equations) to describe electromagnetic oscillation systems using, inter alia, some of the concepts
mentioned in the first part of the paper
The Atmosphere as a Part of Detecting System of Cherenkov Telescopes
Get PDFDanas znamo da termički izvori zračenja poput Sunca i običnih zvijezda nisu jedini
izvori zračenja u svemiru. Postoje mnogi netermički izvori koji imaju drukčiji spektar i
drukčije mehanizme nastanka zračenja. Takvi kozmički izvori emitiraju razne vrste
astročestica: elektromagnetsko zračenje svih frekvencija, kozmičko zračenje (jezgre atoma
visokih energija), astrofizičke neutrine te gravitacijske valove. Oni su povezani s kompaktnim
kozmičkim objektima: neutronskim zvijezdama i crnim rupama. Atmosfera štiti život na
Zemlji od štetnog zračenja na način da zaustavlja astročestice vrlo visokih energija koje
dolaze do Zemlje. Najčešće su to protoni i kozmičke gama-zrake, a možemo ih opažati s
površine Zemlje preko velikih pljuskova čestica u atmosferi. Čerenkovljev teleskop osnovni
je instrument za posredno opažanje visokoenergijskih kozmičkih gama-zraka pomoću
Čerenkovljenog zračenja koje u atmosferi stvaraju pljuskovi čestica.Today we know that thermal sources of radiation like our Sun and ordinary stars are not the
only sources of radiation in the universe. There are many non-thermal sources that have
different spectra and different mechanisms of radiation. Such cosmic sources emit various
types of astroparticles: electromagnetic radiation of all frequencies, cosmic radiation (high
energy atomic nucleus), astrophysical neutrinos and gravity waves. They are associated with
compact cosmic objects: neutron stars and black holes. The atmosphere protects life on Earth
from harmful radiation by stopping astroparticles with very high energies coming to Earth.
The most common high-energy astroparticles are protons and cosmic gamma-rays, and we
can observe them from the ground using large air showers in the atmosphere. Cherenkov
Telescope is a basic instrument used for indirect observation of the high-energy gamma-rays.
It uses Cherenkov radiation
Human Hearing
Get PDFZnanost koja se bavi proučavanjem zvuka naziva se akustika. Za razvoj akustike prvo je
trebalo objasniti valove i valne pojave. Pojave poput ogiba, odbijanja, loma, rezonancije ili
Dopplerovog efekta koje vrijede za valove mogu se primijeniti i na zvuk, koji je jedna vrsta
vala. Zvuk se prenosi zrakom do vanjskog uha, u srednjem uhu se pojačava, a u unutarnjem se
pretvara u električni impuls koji putuje živcem do mozga. Kada se govori o sluhu najčešće se
spominje gubitak sluha. Ovisno o oštećenju moguće je poboljšati sluh. Sluh je moguće
povezati s nastavnim jedinicama fizike u osnovnoj školi.The science involved in sound studies is called acoustics. For the development of acoustics, it
the first was necessary to explain waves. Objects such as diffraction, reflection, refraction,
resonance or Doppler effect that applies to waves can also be applied to sound, which is a
kind of the wave. The sound is transmitted by the air to the outer ear, in the middle ear is
amplified, and internally it turns into an electric impulse that travels by nervous to the brain.
When talking about hearing, mostly it refers to hearing loss. Depending on the damage, it is
possible to improve the hearing. It is possible to associate the hearing with the teaching units
of physics in elementary school