Science & Technology GK Questions with Answers

The correct answer is C, Chandipur, Odisha. Prithvi II is test-fired from the Integrated Test Range at Chandipur on the Odisha coast, the DRDO range used for missile and rocket trials. Prithvi II is a surface-to-surface short-range ballistic missile of the Indian Air Force, developed under the Integrated Guided Missile Development Programme that Dr A.P.J. Abdul Kalam led. It runs on liquid propellant, has a range of about 350 km and can carry a warhead of 500 to 1,000 kg. Option A is wrong because Rutland Island in the Andamans has no missile test range. Option B is wrong because Sriharikota in Andhra Pradesh is ISRO's launch centre for satellites, not a missile range. Option D is wrong because Machilipatnam is a coastal town with no such facility. Exam tip: the IGMDP missiles are Prithvi, Agni, Trishul, Akash and Nag; missiles are tested at Chandipur, while satellites go up from Sriharikota.

The correct answer is D, 1.6 W/kg. The Specific Absorption Rate measures how much radio energy from a handset the body takes in, in watts per kilogram of tissue. From 1 September 2012 the Department of Telecommunications made 1.6 W/kg, averaged over one gram of human tissue, the limit for every new mobile handset design sold in India. Before that India followed the older figure of 2.0 W/kg averaged over ten grams. The rules also require the SAR value to be printed on the handset and its box, and a buyer can check it by dialling a code given by the maker. India's limit matches the standard used in the United States. Option A is wrong because 1.8 W/kg is not a prescribed limit anywhere. Option B is wrong because 2.1 W/kg is not a SAR standard. Option C is wrong because 2.2 W/kg is only a distractor. Exam tip: India's SAR limit is 1.6 W/kg over 1 gram of tissue, in force from 1 September 2012.

The correct answer is C, the European Ariane rocket. The full name of the satellite, Ariane Passenger Payload Experiment, contains the answer, since it flew as a passenger on an Ariane launch in 1981 to test the building of a geostationary communication satellite in India. India then had no vehicle able to reach a geostationary transfer orbit.

Option A, SLV-3, could place only about 40 kg in a low earth orbit and could never have carried APPLE to the height a communication satellite needs. Option B, a Soviet vehicle, had launched Aryabhata in 1975 and Bhaskara in 1979, so it is a reasonable guess but the wrong one here. Option D, the Space Shuttle, carried the later INSAT-1B in 1983, which is a separate fact often asked alongside. The bullock cart photograph of APPLE at the test site is from this programme.

The correct answer is B, the Airports Authority of India. GAGAN stands for GPS Aided GEO Augmented Navigation and was developed by ISRO together with the Airports Authority so that civil aircraft in Indian airspace get position information accurate and reliable enough for approach and landing. It does not have navigation satellites of its own; it broadcasts corrections that improve the signals already available.

Option A, the Indian Air Force, uses satellite navigation but is not the partner in this civil aviation project. Option C, the India Meteorological Department, works on weather and uses satellite data of a different kind. Option D, the Directorate General of Shipping, deals with merchant shipping, and marine users are served by NavIC rather than by GAGAN. The distinction worth carrying into the hall is that NavIC provides signals while GAGAN only corrects them.

The correct answer is C, China. BeiDou is the Chinese global navigation satellite system, built in phases and now offering worldwide coverage, and the name is the Chinese term for the constellation of the Big Dipper.

Option A, Japan, operates QZSS, the Quasi-Zenith Satellite System, which like NavIC is regional rather than global. Option B, Russia, operates GLONASS, the successor of the Soviet system of the same design. Option D, the European Union, operates Galileo, a civil global system deliberately kept outside military control. Add GPS of the United States and India's NavIC and the list is complete, with only NavIC and QZSS being regional. Examiners ask this as a simple pair matching question, so learn the five names with their owners, and remember that the general term for all of them is a global navigation satellite system.

The correct answer is B, IRS-1A, launched in 1988, which began the Indian Remote Sensing series and was the first such satellite whose data was used routinely for crop assessment, forest mapping, water resources and land use rather than only for experiment.

Option A, Bhaskara-1 of 1979, was the first experimental earth observation satellite, and the word experimental is what separates it from IRS-1A, so read the stem carefully. Option C, Cartosat-1 of 2005, gave high resolution imagery for mapping and came much later in the same programme. Option D, RISAT-1 of 2012, was the first indigenous radar imaging satellite, able to see through cloud and work at night. The order to keep is Bhaskara experimental, IRS operational, Cartosat mapping, RISAT radar, and note that the data from this family is received and distributed by the National Remote Sensing Centre at Hyderabad.

The correct answer is B, the first Lagrange point, L1, of the sun and earth system, about 1.5 million kilometres from the earth towards the sun. A Lagrange point is a place where the gravitational pulls of the two bodies and the orbital motion balance, so a spacecraft can stay there with very little fuel, and from L1 the sun can be watched continuously without eclipse or occultation. Aditya-L1 was launched on 2 September 2023 by a PSLV.

Option A, L2, lies on the far side of the earth from the sun and is used by telescopes that look away from the sun. Option C is wrong because the spacecraft orbits a point in the sun-earth system, not the sun itself. Option D would put it in earth orbit, where the earth would block the view for part of every day, which is precisely what the mission had to avoid. Remember the pair: L1 for solar watching, 1.5 million km.

The correct answer is B, a dedicated multi-wavelength space observatory. Astrosat was launched on 28 September 2015 by a PSLV and carries instruments that observe the same cosmic source in the ultraviolet, the visible and the X-ray bands at the same time, which is what multi-wavelength means and what makes the mission unusual among space telescopes of its size.

Option A describes the RISAT series, which images the ground through cloud and at night using radar. Option C describes the IRNSS and NVS satellites of the NavIC constellation. Option D describes EDUSAT of 2004, the first Indian satellite meant only for education and classroom broadcasting. Two other science missions belong in the same list of firsts: Aditya-L1 of 2023, the first solar observatory, and XPoSat of 2024, which studies the polarisation of cosmic X-rays.

The correct answer is B, Kalpana-1. Launched in 2002 as METSAT, it was the first Indian satellite built only for weather work, and it was renamed Kalpana-1 in memory of Kalpana Chawla, the India-born astronaut who died in the Columbia accident of 2003. Its instruments watched cloud cover, water vapour and sea surface temperature for cyclone warning.

Option A, INSAT-1B of 1983, carried meteorological instruments but was primarily a communication satellite, which is the distinction the word exclusively tests. Option C, Bhaskara-2, belonged to the early experimental earth observation series of 1979 and 1981. Option D, Oceansat-1 of 1999, studied the sea, its colour and winds over it, so it is an ocean rather than a weather satellite. The later dedicated weather satellites in this line are the INSAT-3D series.

The correct answer is B, seven. The system was designed as a constellation of seven satellites, three of them in geostationary orbit and four in geosynchronous orbits inclined to the equatorial plane, a small number being enough because the service area is regional and not global. IRNSS-1G, launched in April 2016, completed the seven.

Option A, four, is the number of inclined satellites alone and is the trap for a candidate who remembers the split but not the total. Option D, twenty-four, is roughly the size of a global constellation such as GPS, which needs satellites spread over the whole earth. Option C, nine, matches no system. Remember the split as three plus four, and remember that the second-generation NVS satellites are replacing the first-generation ones as they age.

The correct answer is A, Navigation with Indian Constellation. The name was given in 2016 to the Indian Regional Navigation Satellite System, IRNSS, when the seventh satellite of the constellation was placed in orbit, and the word navik also carries the sense of a sailor or navigator, which is why it was chosen.

Options B, C and D are invented expansions of the kind an examiner adds to see whether the candidate has read the term or only heard it. The two facts that go with the full form are that NavIC is the Indian system built so that the country does not depend on another nation's signals, and that it is a regional system covering India and a belt of about 1,500 km beyond its boundary rather than the whole earth. Keep IRNSS and NavIC as the old and new names of one system.

The correct answer is B, Aryabhata in 1975. It was launched on 19 April 1975 by a Soviet launch vehicle, since India had no vehicle of its own at the time, and it carried experiments in X-ray astronomy, solar physics and the ionosphere. It was named after the ancient Indian mathematician and astronomer.

Option A, Rohini of 1980, holds a different record: it was the first satellite placed in orbit by an Indian launch vehicle, SLV-3, on 18 July 1980, and candidates who mix the two records choose it. Option C, Bhaskara-1 of 1979, was the first experimental earth observation satellite. Option D, APPLE of 1981, was the first experimental communication satellite and went up on the European Ariane rocket. The clean chain to memorise is 1975 first satellite, 1979 first earth observation, 1980 first Indian launch, 1981 first communication satellite.

The correct answer is A, the SSLV, or Small Satellite Launch Vehicle. It has three solid stages and a small liquid velocity trimming module, carries up to about 500 kg to a 500 km low earth orbit, and is designed to be assembled and launched by a small team within days so that a customer with one satellite need not wait for a shared ride.

Option B, PSLV-CA, is the core-alone version of the PSLV flown without strap-on motors; it is a lighter configuration of a large rocket, not a small vehicle in its own right. Option C, ASLV, was an experimental vehicle of the 1980s and 1990s with a capacity of about 150 kg and is no longer in service, so it cannot be the answer to a question about a current vehicle. Option D, LVM3, is at the opposite end of the family as India's heaviest operational rocket.

The correct answer is C, GSLV-D5 in January 2014. That flight carried the GSAT-14 communication satellite and was the first success of the indigenous cryogenic upper stage, which put India among the small group of countries able to build such an engine. Cryogenic technology is hard because liquid hydrogen must be held near minus 253 degrees Celsius and pumped into a running engine.

Option A, GSLV-D1 of April 2001, was the vehicle's first flight and used a Russian-supplied cryogenic stage, not an Indian one. Option B, GSLV-D3 of 2010, was the first attempt to fly the Indian stage and it failed, so the flight is remembered as the attempt rather than the success. Option D, the first orbital flight of LVM3 in June 2017, used the larger C25 cryogenic stage and came three years after the technology had already been proved on GSLV-D5.

The correct answer is A, the Vikram Sarabhai Space Centre at Thiruvananthapuram, ISRO's lead centre for launch vehicle design and development, including solid propulsion, aerodynamics and vehicle structures. Its companion, the Liquid Propulsion Systems Centre, develops the liquid and cryogenic engines that those vehicles fly with.

Option B, the National Remote Sensing Centre at Hyderabad, receives, processes and distributes satellite imagery. Option C, the Master Control Facility at Hassan in Karnataka, does not build anything: it controls geostationary satellites once they are in orbit. Option D, the Physical Research Laboratory at Ahmedabad, founded by Vikram Sarabhai in 1947, carries out space science research and is the cradle of the Indian space programme rather than a rocket factory. Match each centre to one verb: develop, receive, control, research.

The correct answer is C, 104. PSLV-C37 carried the Cartosat-2 series satellite as its main passenger along with two Indian nano-satellites and 101 small foreign satellites, releasing all of them one after another from its restartable liquid fourth stage. The flight is a standing example of the PSLV's ability to serve as a shared ride for many small payloads.

Option A, 36, is the size of a batch of communication satellites carried on a later commercial LVM3 flight, which is why the number feels familiar. Option B, 68, and option D, 140, match no Indian launch. The point examiners test is the combination of vehicle, date and number, so fix the three together: PSLV-C37, 15 February 2017, 104 satellites, with the Cartosat-2 series satellite as the primary payload.

The correct answer is B, the Satish Dhawan Space Centre SHAR at Sriharikota in Andhra Pradesh. It is India's only orbital launch site, on the east coast, so vehicles can fly out eastwards over the Bay of Bengal and take the free gain from the earth's rotation while the spent stages fall harmlessly into the sea. It was earlier called the SHAR Centre and was renamed after Satish Dhawan.

Option A, the Vikram Sarabhai Space Centre, designs and develops launch vehicles but does not launch them, and the nearby Thumba station is used only for small sounding rockets. Option C, the U R Rao Satellite Centre, builds and tests satellites. Option D, the Space Applications Centre, develops the payloads and instruments the satellites carry and works on applications of the data. Learn the four centres as a set of jobs: rocket, launch, satellite, payload.

The correct answer is B, the PSLV. Chandrayaan-1 went up on PSLV-C11 in October 2008 and the Mars Orbiter Mission on PSLV-C25 in November 2013, both in the extended PSLV-XL configuration with six long strap-on motors. Both spacecraft were light enough for the PSLV to place them in a high ellipse from which their own engines raised them towards the moon and Mars.

Option A, GSLV Mk III, now called LVM3, was not yet operational in 2008 and was used later for Chandrayaan-2 and Chandrayaan-3. Option C, SLV-3, could lift only about 40 kg and was retired in the early 1980s. Option D, GSLV Mk II, is meant for communication satellites bound for geostationary orbit and was not used for either interplanetary mission. This pairing of vehicle with mission is the single most asked point in the chapter.

The correct answer is C, the third stage. The GSLV has three stages: a solid core first stage with four liquid strap-on motors, a liquid second stage using a Vikas engine, and a cryogenic upper stage that burns liquid hydrogen with liquid oxygen. A cryogenic stage is placed on top because its very high efficiency matters most once the vehicle is above the thick air and needs the last, largest gain in speed.

Option A is wrong because a cryogenic engine cannot give the heavy thrust needed at lift-off, which is why solid motors do that work. Option B is the liquid Vikas stage, which uses propellants that are liquids at ordinary temperatures and is therefore not cryogenic. Option D does not exist on this vehicle, as the GSLV has only three stages; a fourth stage belongs to the PSLV, and that fourth stage is liquid, not cryogenic.

The correct answer is C, four. The PSLV is unusual in alternating propellants between its stages: the first and third stages burn solid propellant and the second and fourth burn liquid propellant. The liquid fourth stage can be restarted and throttled, which is what lets the vehicle drop satellites into more than one orbit on the same flight.

Option B, three, is the number of stages in GSLV Mk II and in LVM3, and is the answer candidates give when they mix the vehicles up. Option A, two, matches no Indian orbital vehicle. Option D, five, is closer to the Augmented Satellite Launch Vehicle, which is counted as a five-stage rocket because of its strap-on boosters. Note that the six strap-on motors on the larger PSLV versions are not counted as a separate stage, since they burn alongside the first stage.