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Write two uses of x rays class 12

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  1. X-ray images are available immediately, which helps you get answers quickly. Here are the top 3 uses of x-rays. Fractured Bones. Patients who sustain a bone injury are usually asked to undergo x-rays. Even if a fracture is diagnosed without an x-ray, it can still provide significant information about the fracture
  2. Notes for X-Rays chapter of class 12 physics. Dronstudy provides free comprehensive chapterwise class 12 physics notes with proper images & diagram. When a heavy metal target is bombarded with high-energy (30 - 50keV) electrons, it emits X rays. The radiation involves both a continuous and a line spectrum, as shown in the figure
  3. Just like gamma rays, x-rays can't be seen, felt or heard. Instead, they effortlessly pass through skin, bone and metal to produce images that the human eye would never be able to see. Here are some of their most common uses: Broken bones. Today, x-rays are an integral part of contemporary hospitals and medical centres
  4. 8.Write two uses of microwaves. [Foreign 2011] Ans. 9. Write two uses of infrared rays. [Foreign 2011] Ans. 10.Write two uses of X-rays. [Foreign 2011] Ans. 11.What is the frequency of electromagnetic waves produced by oscillating charge of frequency V=10 5 Hz? [Delhi 2011C] Ans. 12.How are infrared waves produced
  5. Class 12 Physics Electrons, Photons and X-rays - Get here the Notes for Class 12 Physics Electrons, Photons and X-rays. Candidates who are ambitious to qualify the Class 12 with good score can check this article for Notes. This is possible only when you have the best CBSE Class 12 Physics study material and a smart preparation plan
  6. e, which is responsible for making DNA. Then remove the two bases and nucleotides are filled in between the gaps

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Physical carcinogens- ionizing radiation like X-rays, gamma rays and non-ionizing radiations like UV radiation of sun. Chemical carcinogens- tobacco smoke and some other chemicals. Biological carcinogens-1. Cancer causing viruses are called oncogenic viruses have genes called viral oncogenes. 2 Infrared Ray Spectroscopy is a technique that can be extensively used to identify molecules by proper analysis of their constituent bonds. If an oscillation can lead to a discrepancy in dipole in the molecule, then it will surely absorb a photon that has a similar frequency to the infrared ray

X-rays are used as a diagnostic tool in medicine and as a treatment for certain forms of cancer. Gamma rays The wavelengths of Gamma rays are from about 10 ‒10 m to less than 10 ‒14 m Ascending order of the em waves ( in terms of frequencies) Radio waves Microwaves X rays Gamma rays. Two uses of any one: Radio waves: Radio and television communication systems; Cellular phones use radio waves to transmit voice communication Microwaves: In microwave ovens ; In radar systems of aircraft navigatio Where. μ 0 is the permeability of free space and is equal to 4π × 10-7 TmA-1.; The direction of the magnetic field is always in a plane perpendicular to the line of element and position vector. It is given by the right-hand thumb rule where the thumb points to the direction of conventional current and the other fingers show the magnetic field's direction Answer: Here P = P 1 + P 2 = + 5 - 3 = + 2 D. Hence f = 1/P = ½ m = + 50 cm. Question 36. Use the maker's formula to write an expression for the (relative) refractive index, μ, of the material in terms of its focal length, f and the radii of curvature, r 1 and r 2, of Its two surfaces There are two types of diffractions. Fresnel Diffraction; Answer: D. A wavelength of X rays ranges from 0.1 to 10mm and yellow light is the range 570 to 590mm. Fringes are formed at nλD/d. Hence the fringes of x-rays are formed close to each other. Class 12. Class 5 Class 6 Class 7 Class 8 Class 9 Class 10 Class 11 Class 12. Start.

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  1. Electromagnetic Waves Class 12 Physics MCQs Pdf. 1. Maxwell in his famous equations of electromagnetism introduced the concept of. 2. The conduction current is same as displacement current when source is. 3. If a variable frequency ac source is connected to a capacitor then with decrease in frequency the displacement current will. 4
  2. X-Rays bring about chemical changes in solution because X-Rays produce highly active radical OH ions in water, which react with the solutes. X-Rays cause the destruction of the fermenting powers of Enzymes; C) Biological Properties: The excitation property of X-Rays is used in the treatment of malignant lesions
  3. The discovery of X-rays by Roentgen in 1895, and of electron by J. J. T in 1897, were important milestones in the understanding of atomic structure. It was found that at sufficiently low pressure of about 0.001 mm of mercury column, a discharge took place between the two electrodes on applying the electric field to the gas in the.
  4. X-rays. In the electromagnetic spectrum, X-rays lie beyond the ultraviolet region. X-rays have wavelengths ranging from about 10-8 m or 10 nm to 10-13 m or 10-4; X-rays are particularly well known due to their use as a diagnostic tool in medicine. Also, the treatment for certain types of cancer involves the use of X-rays
  5. Write two factors justifying the need of modulating a signal. A carrier wave of peak voltage 12 V is used to transmit a message signal. What should be peak voltage of the modulating signal in order to have a modulation index of 75%. Question 16. Write Einstein photoelectric equation
  6. Ultraviolet radiation is just one part of the wider electromagnetic spectrum, which includes radio waves, microwaves, infrared, visible light, x-rays and gamma rays. Ultraviolet is just beyond.

Thus two electrons are gained to complete its octet and hence its valency = 2 Valency of magnesium : it has electronic configuration = 2, 8, 2. Thus, it can lose two electons to attain octet and hence its valency = 2. Question 12. If number of electrons in an atom is 8 and number of protons is also 8, then. what is the atomic number of the atom an CBSE board exam 2020 for Class 12 Physics is scheduled for 02nd March 2020. X - rays. Question: Two particles have equal momenta then the ratio of their Write the basic assumptions used in. isometric class includes (100), (010), (001), (-100), (0-10) and (00-1), while for the triclinic {100} only the (100) is included. d-spacing is defined as the distance between adjacent planes. When X-rays diffract due to interference amongst a family of similar atomic planes, then each diffraction plane may be reference by it's indices d hk X-Rays. Because of their use in medicine, almost everyone has heard of x-rays. X-rays are similar to gamma rays in that they are photons of pure energy. X-rays and gamma rays have the same basic properties but come from different parts of the atom. X-rays are emitted from processes outside the nucleus, but gamma rays originate inside the nucleus Write two different uses of concave mirrors. Answer: Concave mirror are used in. Torches; Searchlights; headlights of vehicles, etc. Question 10. Name the type of mirror which always forms a virtual and diminished image. Answer: Convex mirror. Question 11. Which mirror-convex or concave has a larger field of view? Answer: Convex mirror.

X-Rays - Properties, Definition, Wavelength, Types, Uses

  1. (iv)Gamma rays are used in medical science to kill cancer cells. Question 16 Name the waves (a) of lowest wavelength, (b) used for taking photographs in dark, (c) produced by the changes in the nucleus of an atom, (d) of wavelength nearly 0.1 nm
  2. X-rays are produced by interaction of accelerated electrons with tungsten nuclei within the tube anode. Two types of radiation are generated: characteristic radiation and bremsstrahlung (braking) radiation. Changing the X-ray machine current or voltage settings alters the properties of the X-ray beam. X-rays are produced within the X-ray.
  3. Physics Notes for Class 12 Chapter 9 Ray Optics and optical Instruments Light Light is a form of energy eyes. which produces the Sources of light are of three types- There are two laws of reflection. (i) The incident ray, the reflected ray and the normal at the point of incidence all three lie in the same plane
  4. • Gamma rays are electromagnetic radiation with high frequency. • When atoms decay by emitting a or b particles to form a new atom, the nuclei of the new atom formed may still have too much energy to be completely stable. • This excess energy is emitted as gamma rays (gamma ray photons have energies of ~ 1 x 10-12 J).
  5. Class 12 Physics Ray Optics - Get here the Notes for Class 12 Physics Ray Optics. Candidates who are ambitious to qualify the Class 12 with good score can check this article for Notes. This is possible only when you have the best CBSE Class 12 Physics study material and a smart preparation plan. To assist you with that, we are here with notes
  6. CBSE Sample Paper Class 12 Physics 2018-19 with Solutions and new marking scheme and blueprint for class 12 have been released by CBSE. Draw a labelled ray diagram to show the image formation in a refracting type astronomical telescope in the normal adjustment position. Write two drawbacks of refracting type telescopes. OR

Physics Investigatory Project Class 12 for welding purposes. A step down transformer is used for obtaining large current. A step up transformer is used for the production of X-Rays and NEON advertisement. Transformers are used in voltage regulators and stabilized power supplies. Transformers are used in the transmissions of a.c. over long. CBSE 12 Class Compartment 2019 Paper: 55-1-1 Physics. Question 1) Define the angle of inclination at a given place due to the earth's magnetic field. View Solutions. Question 2) Name the most energetic electromagnetic radiation and write its frequency range She has read that X-rays can cause tissue effects, such as skin reddening and hair loss. Which statement would best inform Sally of the level of risk? The dentist uses X-ray fluoroscopy, which can take enough time to cause those problems. The dentist uses X-ray radiography, which takes too short a time to cause those problems Free Question Bank for 12th Class Physics Nuclear Physics And Radioactivity Nuclei Conceptual Problem X-rays have lower energy than gamma rays because X-rays have shorter wavelengths. Which should he write in the Use section for X-rays? music broadcasts luggage inspections night-vision goggles digital photographs. A student takes notes in class

2 Mention one use of part of electromagnetic spectrum to which a frequency of 4000MHz belongs. OR What physical quantity is same for X- rays of wavelength 10-10 and red light of wavelength 6800 Ao. 1 3 Magnetic field lines can be entirely confined within the core of a toroid, but not within a straight solenoid. Why?. 1 Practice Question Paper - 3 units line segment R X. 7 + 5 + 3 = 15 units of length for C X ¯ Coordinate Plane. A coordinate plane, also called a Cartesian plane (thank you, René Descartes!), is the grid built up from a x-axis and a y-axis. You can think of it as two perpendicular number lines, or as a map of the territory occupied by line segments 5. You may use the following values of physical constants wherever necessary. c = 3 x 10 8ms-1 h = 6.6 x 10-34Js -e = 1.6 x 10 19 C μ o −= 4 π x 107T m A−1 1/4πε o = 9 x10 9 N m 2 / C 2 m e = 9.1 x 10 -31 kg _____ Section - A All questions are compulsory NCERT Solutions for Class 12 Physics in PDF format is given below to free download for new academic session 2021-22 based on latest CBSE Syllabus. For the regular preparation for CBSE, IIT - JEE Mains and Advance, NEET, BITSAT, GGSIPU use latest NCERT books available in the market. A few questions related to these books are given below Free PDF download for Important Questions Class 12 Physics Ch 9 ? Ray Optics and Optical Instruments 3 Marks Questions to score more marks in exams, prepared by expert Subject teachers from the latest edition of CBSE/NCERT books, Important Questions with Answers for CBSE Class 6 to 12 ? All Subjects . (Updated for 2021-2022) Board Exams Score high with CoolGyan and secure top rank in your exams

Physics Project for Class 12. 12th class is a no risk class. It is the class which decide your future. Whether you are going to work in MNC or going to work with usual private firms, it all depends here. To ensure the good marks to students we always stands behind them with all practical and theoretical support on Physics investigatory project Concave and Convex Lenses - The type of lenses which converge the light beam coming from the source to one point on the other side to form an image is called as a convex lens, while the concave lens which is thinner at the centre and gets thicker as we move towards the edges is called as Concave lens Uses of Electromagnetic Waves. Quick revise. Introduction. Wavelength of the ElectroMagnetic spectrum continually changes. high frequency = short wavelength. high frequency = high energy. high energy = more dangerous. The video and text below describe some of the qualities and uses of different waves on the electromagnetic spectrum

Write two other ways to represent this nuclide. e. xerCise. 16.1 - Nuclide Symbols . One of the nuclides used in radiation therapy for the treatment of cancer has 39 . protons and 51 neutrons. Write its nuclide symbol in the form of . Write two other . ways to represent this nuclide. e. xample. 16.2 - Nuclide Symbol List these two rays and state the path of these rays after refraction. Use these two rays to locate the image of an object placed between F and 2F of a convex lens. ( CBSE 2012) Answer: Two rays choose for refraction: A ray of light parallel to the principal axis. A ray of light passing through the optical centre of a lens Use of these online books as a part of digital content packages or software is also strictly prohibited. No website or online service is permitted to host these online textbooks. Links may however be provided with written permission from the NCERT 9. A 12·5 eV electron beam is used to excite a gaseous hydrogen atom at room temperature. Determine the wavelengths and the corresponding series of the lines emitted.(2) 10. Write two properties of a material suitable for making (a) a permanent magnet, and (b) an electromagnet.(2) SECTION C 11 The maximum energy of the produced X-ray photon is limited by the energy of the incident electron, which is equal to the voltage on the tube times the electron charge, so an 100 kV tube cannot create X-rays with an energy greater than 100 keV. When the electrons hit the target, X-rays are created by two different atomic processes: Bremsstrahlung

Free PDF download for Important Questions Class 12 Physics Ch 9 ? Ray Optics and Optical Instruments 5 Marks Questions to score more marks in exams, prepared by expert Subject teachers from the latest edition of CBSE/NCERT books, Important Questions with Answers for CBSE Class 6 to 12 ? All Subjects . (Updated for 2021-2022) Board Exams Score high with CoolGyan and secure top rank in your exams 15 (i) Write two observations when lead nitrate is heated in a test tube. (ii) Name the type of reaction. (iii) Write a balanced chemical equation to represent the above reaction. 3 16 A compound 'X' of sodium is used as an antacid and it decomposes on strong heating. (i) Name the compound 'X' and give its chemical formula A C-arm is an imaging scanner intensifier.The name derives from the C-shaped arm used to connect the x-ray source and x-ray detector to one another. C-arms have radiographic capabilities, though they are used primarily for fluoroscopic intraoperative imaging during surgical, orthopedic and emergency care procedures.The devices provide high-resolution X-ray images in real time, thus allowing.

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First, we draw a ray parallel to principal axis. So, it appears to pass through focus after reflection. We draw another ray which passes through Optical Center. So, the ray will go through without any deviation. Where both reflected rays meet is point A'. And the image formed is A'B'. This image is formed between F 1 and Optical Center (O An angle bisector is defined as a ray that divides a given angle into two angles with equal measures. The word bisector or bisection means dividing one thing into two equal parts. In geometry, we usually divide a triangle and an angle by a line or ray which is considered as an angle bisector write multi‐digit whole numbers using base‐ten numerals, number names, 10 blocks are often used in class to help students grasp number. Base ten blocks have 'a unit' to fraction of the circle arc between the points where the two rays intersect the.

photoelectric effect, phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation.The effect is often defined as the ejection of electrons from a metal plate when light falls on it. In a broader definition, the radiant energy may be infrared, visible, or ultraviolet light, X-rays, or gamma rays; the material may be a solid. Flaws in metals used for structural purposes can be detected using high-energy gamma rays from cobalt-60 in a fashion similar to the way X-rays are used to examine the human body. In one form of pest control, flies are controlled by sterilizing male flies with γ radiation so that females breeding with them do not produce offspring In 1968, the mummy was X-rayed by an anatomy professor, revealed few facts - his breast bone and front ribs were missing. Later, on January 05 2009, Tut was taken for CT (Computed Tomography) scan which takes hundreds of X-Rays and creates a three-dimensional image. The night of the scan, the workmen carried his body from the tomb in a box

Physics MCQs for Class 12 with Answers Chapter 8

Answer: Mass number of helium is equal to its atomic mass but has no units. ∴ Mass number (A) of helium = 4. No. of protons in the nucleus = 2 Atomic number (Z) of the element = 2. No. of neutrons (n) = A - Z = 4 - 2 = 2. Question 9. Write the distribution of electrons in carbon and sodium atoms Table 11.4. 1 lists several radioactive isotopes and their medical uses. In addition to the direct application of radioactive isotopes to diseased tissue, the gamma ray emissions of some isotopes can be directed toward the tissue to be destroyed. Cobalt-60 is a useful isotope for this kind of procedure So we can actually write down a chemical reaction equation for alpha decay: Ra → Rn + He. The radium nucleus (Ra, atomic number 88) breaks up into the helium nucleus (He, the little chunk) and a daughter nucleus that corresponds to the element radon (Rn, atomic number 86) The above diagram shows an electron gun of a hot cathode ray tube, 1. Name the parts X and Y. 2. A 6V d.c. source and a 1000V d.c. source are available. Show how these sources should be connected to the terminals of X and Y so as to obtain a focused beam of fast moving electrons. (ii) Give one use of a cathode ray tube. [4] Answer

Top 3 Uses of X-Rays Independent Imaging South Florid

22 Two waves from two coherent sources S and S' superimpose at X as shown in the figure. If X is a point on the second minima and SX - S'X is 4.5 cm. Calculate the wavelength of the waves. 2 23 Draw the energy band diagram when intrinsic semiconductor (Ge) is doped with impurity atoms of Antimony (Sb). Name the extrinsic semiconductor s Alpha, beta and gamma radiation can be detected by using magnetic field. Alpha and beta particles have contrary charges-they undergo deflection in opposite direction, whereas gamma rays do not transfer any charge-they do not undergo deflection.The displacement laws of radioactivity governed by Rutherford, which are listed below:- (a) During a α decay, the daughter element was always two.

Cathode rays produce heat, when allowed to fall on matter. iv. Cathode rays produce fluorescence when they strike a number of crystals, minerals and salts. v. When cathode rays strike a solid substance of large atomic weight, X-rays are produced. vi. Cathode rays ionize the gas through which they pass. vii. Cathode rays affect the photographic. required for the safe use of the particular dental X-ray equipment. c. Ascertain that dental personnel demonstrate competence in using the X-ray equipment and imaging software, and comply with the radiation safety rules. d. Assure that individuals whose job requires use of X-rays should be provided individual or personnel monitoring devices Case 1 - Object is Placed at infinity. In this Case, Object AB is kept far away from mirror (almost at infinite distance) So, we draw rays parallel to principal axis. Since ray parallel to principal axis passes through the Focus. Both rays meet at focus after reflection. Hence, Image is formed at Focus. And it is very very small. We can say that An x-ray tube functions as a specific energy converter, receiving electrical energy and converting it into two other forms of energy: x-radiation (1%) and heat (99%). Heat is considered the undesirable product of this conversion process; therefore x-radiation is created by taking the energy from the electrons and converting it into photons.This very specific energy conversion takes place in.

Elements of Modern X-ray Physics, 2nd Ed. by Jens Als-Nielsen and Des McMorrow, John Wiley & Sons, Ltd., 2011 (Modern x-ray physics & new developments) X-ray Diffraction, by B.E. Warren, General Publishing Company, 1969, 1990 (Classic X-ray physics book Characteristic X-rays. The atoms of each element in the sample consist of a nucleus made up of neutrons and positively charged protons, and a cloud of negatively charged electrons that surrounds the nucleus. The number of protons in the nucleus of the atom defines its atomic number, Z, while in a neutrally charged atom the number of protons is matched by the number of electrons

Light is a form of energy, which induces the sensation of vision in our eyes and makes us able to see various things present in our surrounding. The light ray may be objects self-light or reflected light. Luminous objects are objects which emit light of their own. E.g., sun, bulb, tubelight, glow worms. Non-luminous objects are objects which. X-ray definition at Dictionary.com, a free online dictionary with pronunciation, synonyms and translation. Look it up now A CAT scan is a special type of x-ray called a Computerized Axial Tomography Scan. A regular x-ray can only provide a two-dimensional view of a particular part of the body. Then, if a smaller bone is hidden between the x-ray machine and a larger bone, the smaller bone cannot be seen. It is like a shadow Lines, Rays, and Angles. This fourth grade geometry lesson teaches the definitions for a line, ray, angle, acute angle, right angle, and obtuse angle. We also study how the size of the angle is ONLY determined by how much it has opened as compared to the whole circle. The lesson contains many varied exercises for students

Chapter Notes: X-Rays Physics Class 12 - DronStudy

X-rays X-rays have even shorter wavelengths than ultraviolet rays. At this point in the electromagnetic spectrum, scientists begin to think of these rays more as particles than waves. X-rays were discovered by German scientist Wilhelm Roentgen. They can penetrate soft tissue like skin and muscle and are used to take X-ray pictures of bones in. From lowest energy to highest energy (red to blue) there are radio waves, microwaves, infrared, visible light, ultraviolet, x-rays and gamma rays. Each of them have their uses and, at the high. (b) Resistors can be used as heating elements in the rear windows of cars. The diagram shows two possible designs. XY (i) Complete the table by placing a tick (9) in the correct boxes. (1) Design Series Parallel X Y (ii) Describe the advantages and disadvantages of design X when used as a heater in a car window. (3 X-Ray. X-Ray's name is pig latin for his given name, Rex. X-Ray wears glasses because he can't see very well, and he always uses the same shovel because he claims it is the shortest one (the holes dug by the boys are measured with their shovels). X-Ray is the unofficial leader of the boys in Group D Answers is the place to go to get the answers you need and to ask the questions you wan

What Are the Uses of X-Rays? Labmate Onlin

For electromagnetic radiation to be diffracted the spacing in the grating should be of the same order as the wavelength In crystals the typical interatomic spacing ~ 2-3 Å so the suitable radiation is X-rays Hence, X-rays can be used for the study of crystal structures Neutrons and Electrons are also used for diffraction studies from materials A ray is a portion of a line with only one end point, as shown below. Its length is still infinite, but it has one identifiable end. When two lines, line segments, rays, or some combination thereof intersect, they form an angle. An example of an angle is shown below. Angles can be measured in degrees (°), which range from 0° to 360° Uses of Beta Radiation. Beta radiation is mainly used in industrial processes such as paper mills and aluminium foil production. A beta radiation source is placed above the sheets coming out of the machines while a Geiger counter, or radiation reader, is placed underneath. The purpose of this is to test the thickness of the sheets Second Formula for Magnification There is another formula of magnification Note : - If magnification (m) is positive , It means image formed is virtual and erect If magnification (m) is negative, It means image formed is real and inverted Questions Example 10.1 - A convex mirror used for rear-view on an automobile has a radius of curvature of 3.00 m Radiation is energy in the form of waves of particles. There are two forms of radiation - non-ionizing and ionizing - which will be discussed in sections 3.1 and 3.2, respectively. 3.1 Non-ionizing radiation . Non-ionizing radiation has less energy than ionizing radiation; it does not possess enough energy to .

Usage of x-rays in hospital use and engineering applications. X-ray photographs are used for medical diagnosis Soft X-rays penetrate flesh more readily than they do bone, which makes X-ray 'shadow' photographs possible. In industry, X-ray photographs are used to check for flaws in welded metal joints. Administrator of Mini Physics Deciding whether to write numbers as numerals or as number words is a matter of style. The style for a literary publication may differ from the style for a journalistic publication. The key in all cases is to use a consistent style throughout your writing. Many publishers of literary works, such as literary journals and [

A monofilament polyethylene thread is tied through the tip, resulting in two white threads, each at least 10.5 cm in length, to aid in detection and removal of the intrauterine system. The T-frame is made of polyethylene with barium sulfate to aid in detecting the intrauterine system under x-ray Cosmic rays can even be used for applications outside of astronomy. In November 2017, a research team discovered a possible void in the Great Pyramid of Giza, which was built around 2560 B.C. Watch anywhere, anytime, on an unlimited number of devices. Sign in with your Netflix account to watch instantly on the web at netflix.com from your personal computer or on any internet-connected device that offers the Netflix app, including smart TVs, smartphones, tablets, streaming media players and game consoles Figure 4a shows the Australia Telescope Compact Array, which uses six 22-m antennas for mapping the southern skies using radio waves. Figure 4b shows the focusing of x rays on the Chandra X-ray Observatory—a satellite orbiting earth since 1999 and looking at high temperature events as exploding stars, quasars, and black holes

Light shows staged with lasers use moving mirrors to swing beams and create colorful effects. Show that a light ray reflected from a mirror changes direction by 2θ when the mirror is rotated by an angle θ. A flat mirror is neither converging nor diverging. To prove this, consider two rays originating from the same point and diverging at an. Search the world's information, including webpages, images, videos and more. Google has many special features to help you find exactly what you're looking for Measuring Radiation Exposure. Several different devices are used to detect and measure radiation, including Geiger counters, scintillation counters (scintillators), and radiation dosimeters ().Probably the best-known radiation instrument, the Geiger counter (also called the Geiger-Müller counter) detects and measures radiation. Radiation causes the ionization of the gas in a Geiger-Müller tube Defects of vision and their correction. The ability to see is called vision. It is also called eyesight. Sometimes the eye of a person cannot focus the image of an object on the retina properly. In such cases the vision of a person becomes blurred and he cannot see either the distant objects or nearby objects (or both) clearly and comfortably. The person is said to have a defect of vision PEChapter 15 Section A Radioactivity OI Introductory. NASA's Chandra X-ray Observatory is a telescope specially designed to detect X-ray emission from very hot regions of the Universe such as exploded stars, clusters of galaxies, and matter around black holes. Because X-rays are absorbed by Earth's atmosphere, Chandra must orbit above it, up to an altitude of 139,000 km (86,500 mi) in space