A mixure of solid Al2O3 and Fe2O3 can be separated by the method of

Q. In a telescope of magnification power 10, the focal length of the objective lens is 60 cm, what will be the total length of eyepiece
  1 6 cm
  2 25 cm
  3 30 cm
  4 50 cm
    Ans:1 

Q. A hollow cylindrical rod is filled with air, to make it a resonance column. To produce a wave of length 48 cm the minimum length of rod should be
  1 12 cm
  2 24 cm
  3 48 cm
  4 96 cm
    Ans:2 

Q. An object is placed between the pole of concave mirror and the focus of the mirror, the image formed will be
  1 Behind the mirror, virtual, erect and magnified
  2 At infinity, real inverted and highly enlarged
  3 Byond centre of curvature, real inverted and enlarged
  4 Beyond 2F, real inverted and enlarged
    Ans:1 

Q. When 1 litre of water freezes, the volume of ice formed will be
  1 0.9 litre
  2 1.0 litre
  3 1.11 litre
  4 1.5 litre
    Ans:3 

Q. A mixure of solid Al2O3 and Fe2O3 can be separated by the method of
  1 Forth floatation
  2 Magnetic separation
  3 Gravity separation
  4 Dissolving in Water
    Ans:2 

Q. A body is thrown vertically upwards with a speed of 100 m/sec. While coming back on ground, its speed at starting point will be
  1 100 m/sec
  2 1000 m/sec
  3 50 m/sec
  4 200 m/sec
    Ans:1 

Q. Which one of the following is not a radioactive element?
  1 Uranium
  2 Radium
  3 Thorium
  4 Cadmium
    Ans:4 

Q. The International date line deviates from 1800 meridian in the North Pacific Ocean due to
  1 Aleutian Islands
  2 Samoa Islands
  3 Fuji Islands
  4 Cook Islands
    Ans:1 

Q. Superconductors are those materials
  1 Which become non-conductors at transition point
  2 Which looses all electrical resistance when cooled below a certain temperature
  3 In which resistance rises to infinity below certain temperature
  4 Which conducts electricity in extra widths
    Ans:2 

Q. Which of the following is a physical change?
  1 Boiling of Water
  2 Rusting of Iron
  3 Boiling of an Egg
  4 Burning of Candle
    Ans:1