Computer Awareness Mixed Quiz: Set 30

The correct answer is C, microwave. Transmission media fall into two families. A guided or bounded medium confines the signal to a solid conductor or light pipe, and the three guided media are twisted pair, coaxial cable and optical fibre. An unguided or unbounded medium sends the signal through air or space with nothing to confine it, and the three unguided media are radio waves, microwaves and infrared. A microwave link therefore belongs to the second family: it is directional, needs a clear line of sight between dish antennas on towers, and is used for long-distance telephone trunks and satellite communication. Option A, coaxial cable, option B, optical fibre, and option D, shielded twisted pair, are all guided media, each with a physical path along which the signal must travel. The quick test is whether a cable has to be laid.

The correct answer is C, C-DAC. The Centre for Development of Advanced Computing was set up at Pune in 1988 with the specific task of building an indigenous supercomputer after India was refused an American Cray machine, and in 1991 its team completed PARAM 8000, a parallel computer assembled from transputer processors. Option A is wrong because the Indian Space Research Organisation built the SAGA-220 system in 2011, using graphics processors, long after PARAM. Option B is wrong because the Bhabha Atomic Research Centre developed the ANUPAM series of parallel computers, a separate line of work for atomic energy. Option D is wrong because within the Defence Research and Development Organisation it was ANURAG at Hyderabad that built PACE, the Processor for Aerodynamic Computation and Evaluation. C-DAC also built AIRAWAT at Pune for artificial intelligence work, which is its newest well known system.

The correct answer is A, Long Term Evolution. LTE is the radio access technology of fourth generation mobile networks, standardised by the Third Generation Partnership Project. The name records the intention of the standard bodies to let the existing GSM and UMTS networks evolve over the long term towards an all-IP system rather than be replaced overnight, and voice over LTE later brought ordinary calls on to the same data network. Option B, Last Time Evolution, is not a term used anywhere in telecommunications. Option C, Least Time Evolution, is likewise invented and has no technical meaning. Option D, Long Time Evolution, is the commonest wrong choice because it differs from the right answer by a single word, but the standard uses the word term, not time. Candidates should remember LTE with 4G and New Radio with 5G.

The correct answer is B, George Boole, the English mathematician who in the middle of the nineteenth century showed that logical reasoning could be written as an algebra on just two values, true and false. The system was a work of pure mathematics for decades until Claude Shannon showed that it described electrical switching circuits exactly, which opened the way to digital computing. A is wrong because Charles Babbage designed the Difference Engine and the Analytical Engine and is called the father of the computer, but he worked on mechanical calculation, not on logic as algebra. C is wrong because Blaise Pascal built an early mechanical adding machine, the Pascaline, in the seventeenth century. D is wrong because John von Neumann gave the stored-program architecture in which instructions and data share the same memory, a much later contribution. Pair the names carefully: Boole for the algebra, Shannon for its use in circuits, Karnaugh for the simplification map.

The correct answer is A, Joint Photographic Experts Group. JPEG is named after the committee of the International Organization for Standardization and the International Telecommunication Union that drew up the standard for compressing continuous tone photographs. Its compression is lossy, which means some detail is thrown away for a much smaller file, and it keeps no transparency, so a JPEG logo always carries a background. Option B is wrong because the format has nothing to do with the Java language and predates it in design work. Option C invents an expansion around the word pixel, which is tempting but is not the committee's name. Option D is also invented, and candidates should note that the format is about compression rather than editing. Remember the pair: JPEG for photographs with lossy compression, PNG for lossless images with transparency.

The correct answer is C, Graphics. In multimedia, graphics is the broad word for every kind of visual element a computer can store and show, so drawings, photographs, movies and simulations all sit inside it. The usual list of multimedia elements is text, graphics, audio, video and animation, and in that list graphics covers both pictures made by hand on the screen and pictures captured from the real world. Graphics are stored either as bitmaps, made of pixels, as in a JPEG or BMP photograph, or as vectors, made of lines and curves described by equations, as in a drawing or a CAD file. A is wrong because animation is only one kind of visual, a sequence of frames shown fast enough to look like movement. B is wrong because an image is a single still picture, so it is narrower than the four things listed. D is wrong because text is made of characters and carries no picture. Exam tip: multimedia elements are text, graphics, audio, video and animation; bitmap graphics use pixels, vector graphics use equations.

The correct answer is C, C-DAC and IISc Bengaluru. The National Supercomputing Mission, approved in 2015, is steered jointly by the Ministry of Electronics and Information Technology and the Department of Science and Technology, and it is implemented by the Centre for Development of Advanced Computing at Pune together with the Indian Institute of Science at Bengaluru. Option A is wrong because ISRO and DRDO build computers for their own space and defence needs, such as SAGA-220 and PACE. Option B is wrong because BARC's ANUPAM series serves atomic energy and the National Informatics Centre runs government networks. Option D is wrong because NIC and ERNET India are network and e-governance bodies, not builders of supercomputers. The mission's aims are to install systems, to make the hardware in India and to train users.

The correct answer is D, the input tag with its type attribute set to checkbox. HTML has no separate checkbox element at all. Every simple form control is written with the single input tag, and the type attribute decides what the browser draws, whether that is text, password, radio, checkbox, submit, file or hidden. So a checkbox is made by writing input and setting type to checkbox, while the name and value attributes tell the server which boxes were ticked. Several checkboxes may share one name, which lets a user pick more than one answer; radio buttons that share a name allow only one choice. Option A is wrong because checkbox is written there as a bare word instead of as the value of the type attribute. Option B is wrong because no checkbox element exists in HTML. Option C is wrong because the equals sign is placed straight after the tag name rather than inside a proper attribute. Exam tip: one input tag, many controls, and the type attribute is what changes.

The correct answer is C, infrared. Infrared lies just below visible light in frequency, and like visible light it is stopped by an ordinary wall. Its range is only a few metres and it needs a nearly clear path between the transmitter and the receiver, which is exactly the arrangement in a remote control pointed at a television set. That same limitation is an advantage inside a room, because a neighbour s remote cannot interfere with yours and the signal cannot be intercepted from outside. Option A, radio waves, pass easily through walls and travel far, which is why they serve broadcasting and mobile telephony. Option B, microwaves, need line of sight over long distances and are used in tower-to-tower and satellite links, not in remotes. Option D, very low frequency waves, have enormous wavelengths, penetrate sea water and are used for submarine communication.

The correct answer is C, C2B. In the consumer-to-business model the consumer names the price or the terms and the business then accepts or declines the offer, so the usual direction of an offer is reversed. Reverse-auction travel sites, where a traveller bids a price for a hotel room, and freelancers who quote their own rate to companies are everyday examples. The model spread with the internet, which let one individual reach many firms at once. A is wrong because B2B commerce is trade between two businesses, such as a parts maker supplying a car factory. B is wrong because B2C commerce is a business selling directly to the end consumer, as a shopping website does. D is wrong because C2C commerce links one consumer with another through a platform, as online classified and resale sites do. Exam tip: read the pair in order - the first letter is who makes the offer, the second is who responds, so in C2B the consumer sets the price.

The correct answer is B, duplexing. A telephone conversation requires both parties to speak and listen at the same time, so a mobile link must carry traffic in both directions together. That arrangement is called duplexing, and cellular systems achieve it either by using two separate frequency bands, known as frequency division duplex, or by alternating very rapidly between sending and receiving on one band, known as time division duplex. Option A, triplexing, is not a recognised mode of mobile communication. Option C is wrong because the correct term for one-way communication is simplex, not simplexing, and a simplex link such as a broadcast cannot support a phone call. Option D, quadraplexing, is not a term in mobile standards at all. Only duplex and its two forms appear in the syllabus of cellular communication.

The correct answer is B, 1971. The Intel 4004 placed an entire processing unit on a single chip for the first time in a commercial product, and that step marks the beginning of the fourth generation of computers, built on very large scale integration. Everything that followed, including the personal computer, rests on it.

Option A, 1964, is the year of the IBM System 360, a landmark third-generation machine built on integrated circuits, which is why the year appears as a distractor. Option C, 1975, is associated with the early hobby computers of the microprocessor era but not with the 4004 itself. Option D, 1981, is the year the IBM Personal Computer was launched, a fourth-generation product rather than the first microprocessor. The safe way to remember the chain is 1947 transistor, 1958 integrated circuit, 1971 microprocessor.

The correct answer is C, GIF. The Graphics Interchange Format, introduced by CompuServe, can store several frames in one file together with the delay between them, which is why short looping animations on the web were long made as GIFs. It uses lossless LZW compression, allows one transparent colour and is limited to a palette of 256 colours, so photographs look banded in it. Option A, BMP, is Microsoft's plain uncompressed bitmap and holds a single still image. Option B, TIFF, can hold multiple pages for scanning and printing but is not used to play animation. Option D, JPEG, is a lossy single frame photographic format with no animation and no transparency. For the exam, link GIF with 256 colours and animation, and PNG with transparency without animation.

The correct answer is A, Douglas Engelbart. He built the first mouse, a small wooden box with a pair of wheels underneath, at the Stanford Research Institute, and the patent describes it as an X-Y position indicator for a display system. The name stuck because the wire coming out of the back looked like a tail.

Option B, Charles Babbage, designed the Difference Engine and the Analytical Engine in the nineteenth century and is called the Father of the Computer, a completely different title. Option C, Jack Kilby, demonstrated the first integrated circuit and belongs to the generations chapter, not to input devices. Option D, Christopher Latham Sholes, perfected the mechanical typewriter and gave us the QWERTY keyboard layout, so he is the right answer to a keyboard question and a tempting wrong one here. Keep one invention fixed against each name.

The correct answer is B, weather and climate modelling. Pratyush was installed at the Indian Institute of Tropical Meteorology in Pune in 2018, with a companion system, Mihir, at the National Centre for Medium Range Weather Forecasting, and the pair was acquired to run high-resolution models for monsoon forecasting, cyclone tracks and climate studies. Option A is wrong because nuclear simulation is done on the ANUPAM systems of the Bhabha Atomic Research Centre. Option C is wrong because satellite image processing is handled by ISRO's own computing facilities, including SAGA-220. Option D is wrong because genome work uses institutional clusters and the systems of the National Supercomputing Mission rather than a dedicated weather machine. Remember the pairing: Pratyush at Pune and Mihir at Noida, both for weather. Mihir takes its name from a word for the sun, and Pratyush from a word for the first light of day.

The correct answer is D, Ctrl + F2. Ctrl together with F2 opens the print area of the Backstage view in Excel, Word and PowerPoint, where the page is shown exactly as it will be printed and the printer, copies, orientation and margins can be set. In Office 2003 and earlier the same combination opened the older Print Preview window.

Option A, Alt + Ctrl + F2, opens a file rather than previewing one, working like Ctrl + O. Option B, Alt + F2, was the Save As shortcut of very old Office versions and does nothing useful today; the modern Save As key is F12. Option C, Shift + F2, adds or edits a comment on the active cell in Excel, which is a completely different job. Learning the F2 family together helps: F2 alone edits the active cell, Shift + F2 handles a comment, Ctrl + F2 previews the print, and Alt + equals inserts a SUM.

The correct answer is B, copper conductor, insulator, braided shield, plastic jacket. A coaxial cable is built around a single solid or stranded copper wire at the axis, which carries the signal. Around it lies a dielectric insulator that holds the conductor exactly in the centre and sets the electrical properties of the cable. Over that comes a braided or foil metal shield, which acts as the return path and keeps external interference out. The outermost layer is a tough plastic jacket that protects everything from moisture and damage. The name coaxial comes from the conductor and the shield sharing one axis. Option A puts the shield at the centre, option C puts the insulator first and leaves the shield outside the jacket, and option D is simply the correct order reversed, describing the cable from the outside inwards. The usual connector for this cable is the BNC.

The correct answer is A, Subscriber Identity Module. The SIM is a small smart card issued by the operator that stores the subscriber identity, the authentication keys used to prove that identity to the network, and a limited amount of contact and message data. Because the identity lives on the card, a subscriber can move the number to another handset simply by moving the card. Option B, Single Identity Module, resembles the right answer but is not the standard expansion. Option C, Subscriber Internet Module, is wrong because the card is not tied to internet service; it authenticates voice, message and data service alike. Option D, Secure Identity Memory, is invented, although the card is indeed a secure element. Note the contrast with the IMEI, which identifies the handset rather than the subscriber.

The correct answer is B, MPEG-1 Audio Layer III. MPEG stands for Moving Picture Experts Group, and the group defined three audio layers of rising complexity within its MPEG-1 standard; the third layer gave the file extension .mp3. Its compression is lossy and relies on psychoacoustics, discarding sounds a listener is unlikely to hear, which shrinks a recording to roughly a tenth of its uncompressed size. Option A is invented and no standard uses the phrase multi phase audio. Option C sounds plausible because MIDI really is a music protocol, but MIDI and MP3 are different things: MIDI stores instructions, MP3 stores compressed sound. Option D confuses the format with Microsoft's media player software, which plays many formats but gives its name to none of them. Candidates should also keep the companion full forms ready, since MPEG-2 underlies DVD video and MPEG-4 Part 14 gives the familiar MP4 container.

The correct answer is A, floating point operations per second. A supercomputer's performance is stated in FLOPS, the number of floating point calculations it completes in a second, which is why the figures appear as teraflops, petaflops and exaflops; a petaflop is a thousand trillion such operations a second. Option B is wrong because bits per second measures the rate at which data moves over a communication link, not computing speed. Option C is wrong because hertz measures the clock frequency of a single processor, and a supercomputer's strength comes from thousands of processors working in parallel rather than from a high clock speed. Option D is wrong because bytes per instruction is not a performance measure at all. The work that needs such speed includes weather forecasting, drug design and the training of large artificial intelligence models.