Q.31)-Which of the following liquid is most viscous?
  • Oil
  • Milk
  • Water
  • Petrol
Q.32)-The surface tension of water on adding detergent to it
  • Increase
  • Decreases
  • No change
  • Become zero
Q.33)-Rise of oil in a wick is due to
  • Density of the oil
  • Viscosity of the oil
  • Surface tension of the oil
  • Pressure of the oil
Q.34)-If an ordinary glass tube and a glass capillary tube are both dipped in a beaker of water rises in
  • Both
  • Only the glass tube
  • Only the capillary tube
  • Radiation
Q.35)-two rods, one of copper and other of steel, experience the same upthrust when placed in water. Thus both have
  • Equal volume
  • Equal weight
  • Equal density
  • Equal mass
Q.36)-A single fixed pulley is used to draw water from a well because
  • Efficiency is 100%
  • Velocity ratio is low
  • Mechanical advantages is high
  • Force is applied in a convenient direction
Q.37)-Ball pen functions on the principle of
  • Viscosity
  • Boyle's law
  • Gravitional force
  • Surface tension
Q.38)-Water from soil enters into the root hairs owing to
  • Atmospheric pressure
  • Capillary pressure
  • Root pressure
  • Osmatic pressure
Q.39)-Water drops cannot stick to the oily surface due to
  • Lack of adhesive force
  • Surface tension
  • Cannot mix each other
  • Water is lighter than oil
Q.40)-If cream is removed from milk, its density
  • Increases
  • Decreases
  • Remains the same
  • May increase or decrease