81.
Which of the following is not a property of heavy water ?

83.
Small bubbles are perfectly spherical because of

84.
Pitot tube is used to measure

85.
A spherical ball made of steel when dropped in mercury container

86.
If cream is removed from milk, its density

87.
A falling drop of rain water acquires the spherical shape due to

88.
Why the needle of iron swims on water surface when it is kept gently ?

89.
Rise of oil a wick is due to

90.
Bubbles of air rise up through liquids due to