Science and Technology


  1. Which of the following is the first missile which has been developed in India?









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    The Government of India launched the Integrated Guided Missile Development Program in 1983 to achieve self sufficiency in the development and production of wide range of Ballistic Missiles, Surface to Air Missiles etc. Prithvi was the first missile to be developed under the Program. DRDO attempted to build Surface-to-air Missile under Project Devil. The Prithvi missile project encompassed developing 3 variants for use by the Indian Army, Indian Air Force and the Indian Navy. Over the years these specifications underwent a number of changes. While the codename Prithvi stands for any missile inducted by India into its armed forces in this category, the later developmental versions are codenamed as Prithvi II and Prithvi III. Prithvi I class was a surface-tosurface missile having a maximum warhead mounting capability of 1,000 kg, with a range of 150 km. It has an accuracy of 10 – 50 metres and can be launched from Transporter erector launchers. This class of Prithvi missile was inducted into the Indian Army in 1994.

    Correct Option: B

    The Government of India launched the Integrated Guided Missile Development Program in 1983 to achieve self sufficiency in the development and production of wide range of Ballistic Missiles, Surface to Air Missiles etc. Prithvi was the first missile to be developed under the Program. DRDO attempted to build Surface-to-air Missile under Project Devil. The Prithvi missile project encompassed developing 3 variants for use by the Indian Army, Indian Air Force and the Indian Navy. Over the years these specifications underwent a number of changes. While the codename Prithvi stands for any missile inducted by India into its armed forces in this category, the later developmental versions are codenamed as Prithvi II and Prithvi III. Prithvi I class was a surface-tosurface missile having a maximum warhead mounting capability of 1,000 kg, with a range of 150 km. It has an accuracy of 10 – 50 metres and can be launched from Transporter erector launchers. This class of Prithvi missile was inducted into the Indian Army in 1994.


  1. What is a supernova?









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    The Supernova is a stellar explosion that is more energetic than a nova. The explosion expels much or all of a star’s material. Supernovae can be triggered in one of two ways: by the sudden re-ignition of nuclear fusion in a degenerate star; or by the collapse of the core of a massive star. The core of an aging massive star may undergo sudden gravitational collapse, releasing gravitational potential energy that can create a supernova explosion. Alternatively a white dwarf star may accumulate sufficient material from a stellar companion (either through accretion or via a merger) to raise its core temperature enough to ignite carbon fusion, at which point it undergoes runaway nuclear fusion, completely disrupting it.

    Correct Option: B

    The Supernova is a stellar explosion that is more energetic than a nova. The explosion expels much or all of a star’s material. Supernovae can be triggered in one of two ways: by the sudden re-ignition of nuclear fusion in a degenerate star; or by the collapse of the core of a massive star. The core of an aging massive star may undergo sudden gravitational collapse, releasing gravitational potential energy that can create a supernova explosion. Alternatively a white dwarf star may accumulate sufficient material from a stellar companion (either through accretion or via a merger) to raise its core temperature enough to ignite carbon fusion, at which point it undergoes runaway nuclear fusion, completely disrupting it.



  1. The orbits of planets around the sun may be











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    The orbit of a planet around the Sun is an ellipse, with the Sun in one of the focal points of the ellipse. [This focal point is actually the barycenter of the Sunplanet system; for simplicity this explanation assumes the Sun’s mass is infinitely larger than that planet’s.] Within a planetary system, planets, dwarf planets, asteroids (a.k.a. minor planets), comets, and space debris orbit the barycenter in elliptical orbits. A comet in a parabolic or hyperbolic orbit about a barycenter is not gravitationally bound to the star and therefore is not considered part of the star’s planetary system. Bodies which are gravitationally bound to one of the planets in a planetary system, either natural or artificial satellites, follow orbits about a barycenter near that planet. Galileo believed that the inertial path of a body around the Earth must be circular. Lacking the idea of Newtonian gravitation, he hoped this would allow him to explain the path of the planets as circular inertial orbits around the Sun. When Newton solved this problem, he showed that there are four possible paths for the planets: circular, elliptical, parabolic and hyperbolic (all are conic curves). The first two curves are closed and the other two are open curves. These results were obtained for the same energy and with the sun at rest.

    Correct Option: E

    The orbit of a planet around the Sun is an ellipse, with the Sun in one of the focal points of the ellipse. [This focal point is actually the barycenter of the Sunplanet system; for simplicity this explanation assumes the Sun’s mass is infinitely larger than that planet’s.] Within a planetary system, planets, dwarf planets, asteroids (a.k.a. minor planets), comets, and space debris orbit the barycenter in elliptical orbits. A comet in a parabolic or hyperbolic orbit about a barycenter is not gravitationally bound to the star and therefore is not considered part of the star’s planetary system. Bodies which are gravitationally bound to one of the planets in a planetary system, either natural or artificial satellites, follow orbits about a barycenter near that planet. Galileo believed that the inertial path of a body around the Earth must be circular. Lacking the idea of Newtonian gravitation, he hoped this would allow him to explain the path of the planets as circular inertial orbits around the Sun. When Newton solved this problem, he showed that there are four possible paths for the planets: circular, elliptical, parabolic and hyperbolic (all are conic curves). The first two curves are closed and the other two are open curves. These results were obtained for the same energy and with the sun at rest.


  1. At what height, geo-synchronous orbit is located?









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    A geostationary orbit, or Geostationary Earth Orbit (GEO), is a circular orbit 35,786 kilometres above the Earth’s equator and following the direction of the Earth’s rotation. An object in such an orbit has an orbital period equal to the Earth’s rotational period (one sidereal day), and thus appears motionless, at a fixed position in the sky, to ground observers. Communications satellites and weather satellites are often given geostationary orbits, so that the satellite antennas that communicate with them do not have to move to track them, but can be pointed permanently at the position in the sky where they stay. A geostationary orbit is a particular type of geosynchronous orbit.

    Correct Option: D

    A geostationary orbit, or Geostationary Earth Orbit (GEO), is a circular orbit 35,786 kilometres above the Earth’s equator and following the direction of the Earth’s rotation. An object in such an orbit has an orbital period equal to the Earth’s rotational period (one sidereal day), and thus appears motionless, at a fixed position in the sky, to ground observers. Communications satellites and weather satellites are often given geostationary orbits, so that the satellite antennas that communicate with them do not have to move to track them, but can be pointed permanently at the position in the sky where they stay. A geostationary orbit is a particular type of geosynchronous orbit.



  1. Which space-vehicle put man on the moon first time?









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    Apollo 11 was the spaceflight that landed the first humans, Americans Neil Armstrong and Buzz Aldrin, on the Moon on July 20, 1969. Armstrong became the first to step onto the lunar surface 6 hours later on July 21. Armstrong spent about two and a half hours outside the spacecraft, Aldrin slightly less; and together they collected 47.5 pounds (21.5 kg) of lunar material for return to Earth. A third member of the mission, Michael Collins, piloted the command spacecraft alone in lunar orbit until Armstrong and Aldrin returned to it for the trip back to Earth. Launched by a Saturn V rocket from Kennedy Space Center in Merritt Island, Florida on July 16, Apollo 11 was the fifth manned mission of NASA’s Apollo program.

    Correct Option: A

    Apollo 11 was the spaceflight that landed the first humans, Americans Neil Armstrong and Buzz Aldrin, on the Moon on July 20, 1969. Armstrong became the first to step onto the lunar surface 6 hours later on July 21. Armstrong spent about two and a half hours outside the spacecraft, Aldrin slightly less; and together they collected 47.5 pounds (21.5 kg) of lunar material for return to Earth. A third member of the mission, Michael Collins, piloted the command spacecraft alone in lunar orbit until Armstrong and Aldrin returned to it for the trip back to Earth. Launched by a Saturn V rocket from Kennedy Space Center in Merritt Island, Florida on July 16, Apollo 11 was the fifth manned mission of NASA’s Apollo program.