Thursday, December 16, 2010

Universe

11:52 PM Ankur Dubey No comments

Q.  Why is the sky blue?
A.  Violet and blue light have short waves which are scattered more than red light waves. While red light goes almost straight through the atmosphere, blue and violet light are scattered by particles in the atmosphere. Thus, we see a blue sky.
Q.  What are Galileo Satellites?
A.  4 moons of Jupiter
Q.  Who was first to measure the circumference of Earth?
A.  Eratosthenes
Q.  How many other countries have sent moon mission earlier?
A.  Three, India is Fourth
Q.  What does indicate the color of a star?
A.  Its Temperature
Q.  How many minutes does it take for the suns rays to reach earth?
A.  8.4 minutes.
Q.  Who was the first person to walk on the moon?
A.  Neil Armstrong.
Q.  Which planet is known as the ‘Evening Star’?
A.  Venus.
Q.  That is one small step for man, but one giant leap for mankind" Who said this
A.  Neil Armstrong
Q.  What is the colour of the hottest star?
A.  Blue
Q.  Which planet is known as the red planet?
A.  Mars
Q.  When the Earth is very near to Sun in a Year?
A.  1st March
Q.  When the Earth is very far away from the Sun in a Year?
A.  12th December
Q.  The period of one revolution of Sun around the centre of galaxy is called?
A.  Cosmic year
Q.  Sea of Tranquility' and 'Ocean of Storms' are in
A.  Moon
Q.  What is the Sun?
A.  The Sun is just an ordinary star, one of billions of stars in the Universe. The Sun has a special name and is important to us because it is close enough to give Earth light and warmth. This light and warmth is what allows plants, animals and other living things to survive on our planet. Without the Sun there would be no life on Earth.
Q.  How hot is the Sun?
A.  The temperature at the core, or centre, of the Sun is about 16 million degrees Celsius. From the core, this incredible heat energy flows to the surface, where the temperature is closer to 6000 degrees Celsius. This is still so incredibly hot that it would melt anything it touched.
Q.  Why is the Sun so bright?
A.  The Sun is the brightest object in the sky because it is a giant ball of brightly glowing gas. Light from the Sun takes just over eight minutes to reach Earth, but when it gets here it is still so powerful that the light can damage your eyesight. That is why you should never look at the Sun directly and always wear sunglasses on sunny days.
Q.  When do solar eclipses happen?
A.  The Moon travels around Earth. A solar eclipse happens when the Moon comes in between the Sun and the Earth and casts a huge shadow onto the Earth. A total eclipse is rare, but when it happens, the Sun seems to disappear from the sky and for a few moments everything becomes cold and dark.
Q.  What is the solar system?
A.  The Solar system consists of the Sun and the planets that move around the Sun in oval paths called orbits. A planet is a vast ball of rock or gas that travels in orbit around a star. There are other objects in our solar system too, such as moons and asteroids. The Sun is so far away that if you tried to drive there, travelling at 100 kilometers an hour, it would take 170 years to reach your destination!
Q.  How far are we from the Sun?
A.  Earth is 150 million kilometers away from the Sun. this means that our planet is far enough away from the Sun for water to be liquid. If Earth were closer and, therefore, warmer, water would turn to gas, and if it were farther away, water would become ice. It is Earth’s distance from the Sun that makes it the only planet in the solar system that is known to support life.
Q.  Why do planets orbit the Sun?
A.  The planets move around the Sun because the Sun is so big that its gravity is very powerful. Gravity is the force that pulls the planets towards the Sun. it is strong enough to hold all the planets in the solar system in their orbits, moving around the Sun in the same direction.
Q.  When did Earth form?
A.  Earth and the other planets formed about five billion years ago. Our planet was born from dust and gases whirling in orbit around the Sun as it was forming. In the intense heat, the dust and gases collided and hardened into a ball of rock. Even today, Earth is still hit by dust from space and occasional large piece of rock.
Q.  Why does Earth have seasons?
A.  Earth has seasons because it is titled at an angle. This means that as it orbits around the Sun different parts are titled towards the Sun. when the northern hemisphere or top half of the Earth, points to the Sun, this area gets summer. At the same time, the southern hemisphere, or bottom half of the Earth, is pointing away from the Sun and this area experiences its winter.
Q.  What causes night and day?
A.  Night and day happen because Earth rotates, or makes one complete turn, every 24 hours. As well as traveling in an orbit around the Sun, planet Earth spins around its axis, an imaginary line going through the North and South Poles. This means that at any one time, half of Earth is facing the Sun and has daytime, while the other half faces away from the Sun, so it has night.
Q.  What is inside the Earth?
A.  Inside the centre of the Earth there is red-hot, liquid rock. This rock is called magma. The land and oceans at the Earth’s surface lie on an outer layer of cool, hard rock called the crust. The hot magma below rises and sinks slowly in a layer called the mantle. At the very centre of the Earth is a super-hot ball of iron called the core.The earth’s surface is cracked into large pieces, called plates, which fit together like an enormous jigsaw. There are nine large plates and several smaller ones.
Q.  How did the land divide into continents?
A.  The land sits on top of the large pieces, or plates, that make up the Earth’s surface. These plates are slowly moving. Before about 200 million years ago, all the land was joined to form one big continent, or super continent. Over millions of years, as the plates moved, the land split and slowly divided into the seven continents we know today: Africa, Antarctica, Asia, Australia, Europe, North America and South America.
Q.  What Mercury astronaut had a pulse rate of 170 at lift-off-John Glenn, Alan Shepard or Gus Grissom?
A.  Gus Grissom.
Q.  What planet is named after the Greek god who personified the sky?
A.  Uranus.
Q.  What planet is the brightest object in the sky, after the sun and moon?
A.  Venus.
Q.  How old is the universe?
A.  In a study published in the journal Science, a team of researchers says the universe is between 11.2 billion and 20 billion years old.
Q.  What is a black hole?
A.  A black hole is a region of spacetime from which nothing can escape, even light.
Q.  How far is the nearest black hole?
A.  As of now the closest known one is thought to lie at about 1,600 light years from Earth.
Q.  What is a supernova?
A.  A supernova is a stellar explosion which produces an extremely bright object made of plasma that declines to invisibility over weeks or months.
Q.  What is a red giant?
A.  They are stars of 0.4 - 10 times the mass of the Sun which have exhausted their supply of hydrogen in their cores and switched to fusing hydrogen in a shell outside the core.
Q.  What is a solar flare?
A.  A solar flare is an explosion on the Sun that happens when energy stored in twisted magnetic fields is suddenly released.
Q.  What are cosmic rays?
A.  Cosmic rays are high energy charged particles, originating in outer space, that travel at nearly the speed of light and strike the Earth from all directions.
Q.  What is the Van Allen belt?
A.  The Van Allen Radiation Belt is a torus of energetic charged particles (plasma) around Earth, trapped by Earth's magnetic field.
Q.  Which planet has the most moons?
A.  Jupiter has the most of any planet. Saturn is second.
Q.  Which planet is the hottest?
A.  Venus is the hottest planet.
Q.  Which space first was achieved by Toyohiro Akiyama in 1991?
A.  First fare-paying passenger.
Q.  How long did the record-breaking space walk from space shuttle Endeavor last in 1993?
A.  Five hours.
Q.  On which island is the Kennedy Space Center?
A.  Merritt.
Q.  Where did the European space probe Ulysses set off for in 1991?
A.  The Sun.
Q.  What did Neil Armstrong say immediately before "the eagle has landed?"
A.  Tranquility base here.
Q.  Which scientist located Pluto?
A.  Clyde Tombaulgh.
Q.  In what year was Hale Bopp first seen?
A.  1995.
Q.  Which three astronauts died during a launch pad rehearsal in 1967
A.  Gus Grissom, Ed White & Roger Chaffee.
Q.  What is Neil Armstrong's middle name?
A.  Alden.
Q.  What was the name of the Japanese Moon orbiter launched in 1990?
A.  Muses-A.
Q.  Which cosmonaut returned to Earth in 1996 after spending a record-breaking 438 days in space?
A.  Polyakov.
Q.  Whop was the second Soviet cosmonaut?
A.  Titov.
Q.  What was the nationality of the journalist who accompanied a docking mission to MIR in 1990?
A.  Japanese.
Q.  Which planet is the coldest?
A.  Pluto is the coldest planet. It has an icy temperature of -400 F.
Q.  How much would 100 pounds here on earth weigh on the moon?
A.  If you weighed 100 pounds on earth, you would weigh only about 16 pounds on the moon.
Q.  What is Titan's atmosphere made of?
A.  The atmosphere of Titan is made mostly of Nitrogen (80-90%), just like the Earth's atmosphere!
Q.  What is the diameter of the earth?
A.  The diameter of the earth at the equator is 7,926.41 miles (12,756.32 kilometers).
Q.  What is the diameter of the moon?
A.  The diameter of the Moon is 3,474 kilometers.
Q.  How long did Sergei Krikalyev spend on Mir in the early 90s?
A.  Ten months.
Q.  What was the role of Rocco Petrone in the Apollo XI project?
A.  Launch director.
Q.  Who ws the first woman to captain a space shuttle crew?
A.  Eileen Collins.
Q.  How many orbits of the Moon were there on the first manned orbit?
A.  10.
Q.  How fast is the speed of light?
A.  In metric units, the speed of light is exactly 299,792,458 meters per second (or 1,079,252,848.8 km/h). Approximately 186,000 miles per second.
Q.  How many miles is one light year?
A.  A light year is 5,865,696,000,000 miles.
Q.  How long is an astronomical unit?
A.  The Astronomical Unit is the average distance between the Sun and Earth. Its value is 149,597,870 km (about 93 million miles).
Q.  What is the most common element found in the universe?
A.  Hydrogen
Q.  What is Jupiter made of?
A.  Jupiter is about 90% hydrogen and 10% helium (by numbers of atoms, 75/25% by mass) with traces of methane, water, ammonia and "rock"
Q.  How many moons does Jupiter have?
A.  Jupiter has 63 known satellites (as of Feb 2004): the four large Galilean moons plus many more small ones some of which have not yet been named.
Q.  How long is a day on Mercury?
A.  Mercury rotates three times in two of its years.
Q.  How many stars are there in in the big dipper?
A.  The Big Dipper is a group of seven bright stars, 3 which form a handle and 4 which form a bowl.
Q.  How many stars are in the little dipper?
A.  The little dipper has 6 stars.
Q.  What is a constellation?
A.  A constellation is a group of stars that, when seen from Earth, form a pattern.
Q.  How many named constellations are there?
A.  There are 88 constellations.
Q.  What was the name of the first chimpanzee sent into space by America?
A.  Ham
Q.  On what date in 1997 did Pathfinder land on Mars right on schedule?
A.  4th July.
Q.  Who was the next American in space after Shepard?
A.  Virgil Grissom.
Q.  In which year were all three astronauts on the first Moon landing expedition born?
A.  1930.
Q.  Which probe sent back the first major pictures of Jupiter in 1995?
A.  Galileo.
Q.  Who made the first un-tethered space walk of the 1990s?
A.  Mark Lee.
Q.  What was the name of the first probe to send back pictures from Mars?
A.  Viking.
Q.  On which ship did President Nixon welcome the astronauts back from the Moon?
A.  Hornet.
Q.  What is the big red spot on Jupiter?
A.  The Great Red Spot on Jupiter is a hurricane-like storm system. It is large enough that two Earths could fit across it.
Q.  Where is the element gold come from?
A.  Gold only comes from Super Novae.
Q.  What is a parsec?
A.  The parsec is a unit of length used in astronomy, approximately equal to 3.261 light years.
Q.  What is a quasar?
A.  The scientific consensus is that quasars are powered by material falling into super massive black holes in the nuclei of distant galaxies.
Q.  What is a neutron star?
A.  Neutron stars are the collapsed cores of some massive stars.
Q.  What is a brown dwarf?
A.  Brown dwarfs are sub-stellar objects with a mass below that necessary to maintain hydrogen-burning nuclear fusion reactions in their cores.
Q.  What explosive cosmic event was seen with the naked eye in 1987, for the first time in 383 jyears?
A.  A supernova.
Q.  How many of the nine planets have moons?
A.  Seven.
Q.  What mineral accounts for 35 percent of the Earth's composition?
A.  Iron.
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Units Of Measure

11:50 PM Ankur Dubey No comments

Q.  What is the ubit of intensity of light?
A.  Lambert
Q.  What is the unit of pressure?
A.  Pascal
Q.  What is the unit of the wave length of light?
A.  Angstrom
Q.  What is the unit of viscosity of fluid?
A.  Poise
Q.  What is the unit of force?
A.  Dyne
Q.  What is the unit of conductance?
A.  Mho
Q.  What is the unit of angle?
A.  Degree
Q.  What is the unit of depth of the sea?
A.  Fathom
Q.  How much of longitude account for one hour?
A.  15 degree
Q.  'Knot' is the unit of
A.  speed of ships
Q.  One 'Knot' is equivalent to
A.  one nautical mile per hour or approximately 1.85 km per hour
Q.  What is a single unit of quanta called?
A.  A quantum.
Q.  What's a single unit of quanta called?
A.  Quantum.
Q.  What unit of electrical power is equal to one joule per second?
A.  The Watt.
Q.  What's the base unit of mass in the metric system?
A.  The kilogram.
Q.  What unit of measure do you multiply by .39 to convert it to inches?
A.  Centimeters.
Q.  What's the U. S. equivalent of 0.45 kilograms?
A.  One pound.
Q.  What energy unit is defined as the heat required to raise one kilogram of water by one degree Celsius?
A.  One Calorie.
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Physics

11:49 PM Ankur Dubey No comments

Q.  What will be the load experienced for a man with a load jumps from a high building?
A.  Zero, because while falling, both the man and the load are falling at the same acceleration i.e. acceleration due to gravity.
Q.  Why does a ball bounce upon falling?
A.  When a ball falls, it is temporarily deformed. Because of elasticity, the ball tends to regain its original shape for which it presses the ground and bounces up (Newton's Third Law of Motion).
Q.  Why is standing in boats or double decker buses not allowed, particularly in the upper deck of buses?
A.  On tilting the centre of gravity of the boat or bus is lowered and it is likely to overturn.
Q.  Which is more elastic, rubber or steel?
A.  Steel is more elastic for the same stress produced compared with rubber.
Q.  Which one would fall faster among a feather, a wooden ball and a steel ball fall simultaneously in a vacuum?
A.  All will fall at the same speed in vacuum because there will be no air resistance and the earth?s gravity will exert a similar gravitational pull on all.
Q.  When a man fires a gun, he is pushed back slightly. Why?
A.  As the bullet leaves the nozzle of the gun?s barrel with momentum in a forward direction, as per Newton's Third Law of Motion, the ejection imparts to the gun as equal momentum in a backward direction.
Q.  A man with a load jumps from a high building. What will be the load experienced by him?
A.  Zero, because while falling, both the man and the load are falling at the same acceleration i.e. acceleration due to gravity.
Q.  If a feather, a wooden ball and a steel ball fall simultaneously in a vacuum, which one of these would fall faster?
A.  All will fall at the same speed in vacuum because there will be no air resistance and the earth?s gravity will exert a similar gravitational pull on all.
Q.  Why does a man fall forward when he jumps out of a running train or bus?
A.  He is in motion while in the train or bus. When he jumps out, his feet comes to rest while touching the ground but his upper portion which is still in motion propels him forward.
Q.  Why is a compass used as an indicator of direction?
A.  The magnetic needles of a compass under the influence f the earth?s magnetic field lie in a north-south direction. Hence, we can identify direction.
Q.  Curved rail tracks or curved roads are banked or raised on one side. Why?
A.  Because a fast moving train or vehicle leans inwards while taking turn and the banked or raised track provides required centripetal force to enable it to move round the curve.
Q.  What is Physics?
A.  The word 'Physics' comes from the Greek word 'phusis' meaning 'nature', introduced by the ancient scientist 'Aristotle'. Man has always been fascinated by nature. So, he questioned and sought answers for every phenomena nature could offer. The branch of science which is devoted to the study of nature and natural phenomena is called Physics. It is expected that all the events in nature take place according to some basic laws. Physics reveals these basic laws from day-to-day observations.
Q.  Name the scientist who proposed Doppler Effect?
A.  Christian Doppler
Q.  Who discovered the laws of planetary motion?
A.  Johannes Kepler
Q.  Who first proposed the concept of Atomic number?
A.  Henry Moseley
Q.  Sound waves can travel in vacuum. True or false
A.  FALSE
Q.  In a vacuum flask, silvering reduces the loss of heat by
A.  radiation
Q.  The period of oscillation of a pendulum depends on
A.  length of the spring
Q.  Theory of relativity was explained by
A.  Albert Einstein
Q.  Name the scientist who proposed Doppler Effect
A.  Christian Doppler
Q.  Name the scientist who proposed pH value
A.  Sorenson
Q.  Who discovered the Law of Gravitation
A.  Sir Isaac Newton
Q.  A person in a moving vehicle is thrown forward when the vehicle stops suddenly. Why?
A.  When a moving vehicle stops suddenly, a passenger will tend to fall forward because the lower part of his body in contact with the seat comes to stop suddenly but the upper part of his body is still in motion sharing the movement of the train. So on account of inertia, the passenger falls forward.
Q.  What method of arranging elements into related groups was invented by Dimitri Mendeleyev?
A.  The periodic table.
Q.  What physicist remarked: "God is subtle, but he is not malicious"?
A.  Albert Einstein.
Q.  What M-word defines anything that occupies space?
A.  Matter.
Q.  What do you call a substance containing only one kind of atom?
A.  An element.
Q.  What teenager began studying physics after he noticed a chandelier swinging during a 1581 earthquake?
A.  Galileo.
Q.  What elementary particle's antiparticle is the positron?
A.  The electron.
Q.  What element comes last alphabetically?
A.  Zirconium.
Q.  What American physicist pioneered the theory of "black holes" in 1939?
A.  J. Robert Oppenheimer.
Q.  What's a charged atom, with unequal numbers of electrons and protons?
A.  An Ion.
Q.  What theory of physics proposes that energy is not transferred continuously but in discrete amounts?
A.  The quantum theory.
Q.  What element was converted to plutonium in the first nuclear reactors?
A.  Uranium.
Q.  What acronyms for "Weakly Interacting Massive Particles " and "Massive Compact Halo Objects" do physicists use to explain dark matter?
A.  Wimps and Machos.
Q.  What astronomical term gradually replaced the cumbersome "gravitationally completely collapsed object"?
A.  Black Hole.
Q.  What did scientists build in a squash court under a football stadium at the University of Chicago in 1942?
A.  nuclear reactor.
Q.  What's the atomic number of hydrogen?
A.  One.
Q.  What element begins with the letter "k"?
A.  Krypton.
Q.  What F-word is defined in physics as a "nuclear reaction in which nuclei combine to form more massive nuclei"?
A.  Fusion.
Q.  What E-word was the first elementary particle to be discovered?
A.  The electron.
Q.  What's defined as the distance between a lens and its focal point?
A.  It's focal length.
Q.  What founding father was knocked unconscious while attempting to electrocute a turkey?
A.  Benjamin Franklin.
Q.  What three terms are represented in Newton's second law of motion F = ma?
A.  Force, mass, acceleration.
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Non-Metal

11:48 PM Ankur Dubey No comments

Q.  Which non-metals are solid at room temperature?
A.  Carbon, Sulphur and Phosphorus
Q.  Which non-metal is a good conductor of heat & electricity?
A.  Graphite
Q.  Which non-metal is used in water purification process?
A.  Chlorine
Q.  Which non-metal is used to make semi-conductors?
A.  Silicon
Q.  Which non-metal is used for making safety matches and fire works?
A.  Phosphorus
Q.  What is synthetic rubber?
A.  Synthetic rubber made of certain kinds of hydrocarbons. Of these butadiene is the most important. These hydrocarbons are obtained from coal, crude petroleum and alcohol. By the end of the Second World War, the combined production of synthetic rubber by Synthetic rubber is more oil resistant than natural rubber. In the international market, natural rubber is facing severe competition from synthetic rubber.
Q.  What hazardous substance is euphemistically referred to as "mineral fiber"?
A.  Asbestos.
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