60.A balloon ruled with hydrogen will
   (a) continue going upwards uninterrupted
   (b) reach a particular height and remain floating
   (c) burst after reaching some height
   (d) reach a particular height and start coming down
Ans: (b)
61.A piece of cork is embedded inside an ice block which floats in water. What
   will happen to the level of water when all ice melts?
   (a) It will go down
   (b) It will come up
   (c) It will remain at the same level
   (d) First it will go down and it will come up
Ans: (c)
62.When a body is immersed in a fluid the force of buoyancy of the fluid on the
   body depends on
   (a) the immersed volume of the body
   (b) density of the liquid
   (c) acceleration due to the gravity at the place
   (d) All the above
Ans: (d)
63.A pressure gauge for fluids is called
   (a) a hydrometer
   (b) a manometer
   (c) a lactometer
   (d) an anemometer
Ans: (b)
64.The aneroid barometer uses
   (a) mercury
   (b) distilled water
   (c) alcohol
   (d) does not use any liquid
Ans: (d)
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