Universe

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 JupiterQ.  Who was first to measure the circumference of Earth?A.  EratosthenesQ.  How many other countries have sent moon mission earlier?A.  Three, India is FourthQ.  What does indicate the color of a star?A.  Its TemperatureQ.  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...

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Units Of Measure

Q.  What is the ubit of intensity of light?A.  LambertQ.  What is the unit of pressure?A.  PascalQ.  What is the unit of the wave length of light?A.  AngstromQ.  What is the unit of viscosity of fluid?A.  PoiseQ.  What is the unit of force?A.  DyneQ.  What is the unit of conductance?A.  MhoQ.  What is the unit of angle?A.  DegreeQ.  What is the unit of depth of the sea?A.  FathomQ.  How much of longitude account for one hour?A.  15 degreeQ.  'Knot' is the unit ofA.  speed of shipsQ.  One 'Knot' is equivalent toA.  one nautical mile per hour or approximately 1.85 km per hourQ.  What is a single unit of quanta called?A.  A quantum.Q.  What's a single unit of quanta called?A....

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Physics

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...

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Non-Metal

Q.  Which non-metals are solid at room temperature?A.  Carbon, Sulphur and PhosphorusQ.  Which non-metal is a good conductor of heat & electricity?A.  GraphiteQ.  Which non-metal is used in water purification process?A.  ChlorineQ.  Which non-metal is used to make semi-conductors?A.  SiliconQ.  Which non-metal is used for making safety matches and fire works?A.  PhosphorusQ.  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...

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