50.The escape velocity of a satellite projected from the surface of the earth is
   independent of
   (a) the mass of earth
   (b) the mass of the satellite
   (c) the radius of the earth
   (d) gravitation of the earth
Ans: (b)
51.When ice melts, Its volume
   (a) decreases
   (b) increases
   (c) remains the same until all the ice has melted and then increases
   (d) remains the same
Ans: (a)
52.When water is cooled from 4oC to 2oC its density
   (a) increases
   (b) decreases
   (c) remains the same
   (d) first increases then decreases
Ans: (b)
53.When a steel ball is placed on the surface of mercury, it does not sink
   (a) of the surface tension of mercury
   (b) mercury is a semi-solid
   (c) of the high viscosity of mercury
   (d) the density of mercury is greater than that of steel
Ans: (d)
54.A piece of ice is Boating In water kept in a beaker. When all the ice melts
   the level of water will
   (a) first rise and then fall
   (b) fall
   (c) remain the same
   (d) rise
Ans: (c)