This document contains a 9 question quiz about heat engines. Specifically, it asks about the Otto cycle and Diesel cycle processes. The questions cover topics like: the cyclic processes involved in each engine type, when heat exchange and fuel ignition occur, and differences between the two engines. It concludes by providing the answers to the questions.
This document contains a 9 question quiz about heat engines. Specifically, it asks about the Otto cycle and Diesel cycle processes. The questions cover topics like: the cyclic processes involved in each engine type, when heat exchange and fuel ignition occur, and differences between the two engines. It concludes by providing the answers to the questions.
Romania has a population of over 22 million people, with Romanians making up around 89.5% of the population. The capital and largest city is Bucharest, which has a population of over 2 million. Over 86% of Romanians belong to the Orthodox Church, and Romania celebrates its National Day on December 1st. Bucharest is undergoing modernization with a mix of old and new architecture, as it develops its economy and cultural attractions.
X-rays are electromagnetic waves with wavelengths comparable to the size of atoms that are generated when high-speed electrons collide with a metal target in an X-ray tube. X-rays can penetrate materials like human tissue and be detected using devices like gas detectors, proportional counters, and photodetectors. Digital detectors used in medical imaging can detect X-rays and create images of internal structures. X-rays have various medical applications including diagnostic radiography, fluoroscopy, and radiation therapy due to their ability to pass through matter and ionize materials.
Infrared radiation was discovered in the early 19th century by William Herschel. Infrared radiation is an electromagnetic radiation with a wavelength longer than visible light. Infrared radiation includes most of the thermal radiation emitted by objects near room temperature through molecular rotational and vibrational movements. Infrared light is used in various applications like infrared cameras to detect heat loss, observe blood flow, and detect overheating equipment. It also allows astronomy observations of objects obscured by interstellar dust. Night vision devices using infrared illumination allow observation without detection. The Earth absorbs visible and invisible radiation from the sun and re-emits much of the energy as infrared radiation, which is absorbed by greenhouse gases in the atmosphere and re-radiated to warm
This document discusses microwaves and their uses. It begins by noting that James Clerk Maxwell predicted the existence of radio waves in 1864 from his equations. It then discusses how microwaves are generated using specialized vacuum tubes and mentions common devices like magnetrons and klystrons. Examples of applications of microwaves are given as communication, radio, radio astronomy, navigation and power. The most common use of microwaves is in microwave ovens.
This document discusses different devices that can be used to detect ultraviolet radiation, including photodiodes and photomultiplier tubes. It also describes the wavelength ranges of ultraviolet radiation, including UVA, UVB, and UVC. Exposure to UV rays can affect the human body, and UV radiation has various applications like disinfection, medical imaging, and curing polymers.
2. Evolutia aparatelor fotografice. Din timpuri strãvechi si pânã astãzi, la baza tuturor stiintelor, a tuturor descoperirilor mai mari sau mai mici, se aflã observarea fenomenelor naturale, urmatã de o imitatie inteligentã a acestora. Nevoia, spiritul practic, curiozitatea, l-au îndemnat pe om sã imite, sã repete, sã reporducã fenomenele observate în alte conditii, cu mijloace la îndemâna lui, în ajutorul lui .
3. Principiul de functionare al aparatului de fotografiat a fost descoperit de pe vremea artistului si inventatorului Leonardo da Vinci, care a aratat ca pentru a proiecta o imagine este suficient un mic orificiu prin care sa treacă lumina. Cu cat este mai mic orificiul, cu atat imaginea este mai clara. Acest aparat simplu, numit "camera obscura", exista de la inceputul sec. al XVII-lea. Mai mult a durat pana a fost gasit un material fotosensibil pentru a inregistra imaginea respectiva. Aceasta problema a fost rezolvata abia in 1826 cand Joseph Niepce a descoperit ca pentru a produce un bitum sensibil la lumina poate fi folosita clorura de argint .
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5. Pentru a functiona, orice aparat foto, oricat de simplu, trebuie sa aiba urmatoarele parti componente: Corpul - O cutie perfect opaca in care sta filmul pentru a fi expus. Obiectivul - Un dispozitiv care focalizeaza razele de lumina pe film Diafragma - Un dispozitiv care controleaza cata lumina ajunge pe film Obturatorul - Un dispozitiv care controleaza cat timp este filmul expus la lumina Vizorul - Un dispozitiv folosit pentru a incadra eficient imaginea care va fi inregistrata pe film. Sistemul de transport - Un dispozitiv folosit pentru fixarea si transportul filmului.
6. Tipuri de aparate De-a lungul timpului au aparut multe modele de aparate foto, insa marea lor majoritate se incadreaza in una dintre aceste categorii: - aparate cu vizor sau telemetru - aparate cu vizare prin obiectiv (SLR, reflex) - aparate cu doua obiective - aparate cu planfilm