Ans: (c)
432. Separating particles from a suspension is effected by
   (a) centrifugal force
   (b) frictional force
   (c) gravitational force
   (d) distillation
Ans: (a)
433. Which metal is used in storage batteries?
   (a) Copper
   (b) Lead
   (c) Tin
   (d) Iron
Ans: (b)
434. Rain drops acquire spherical shape due to
   (a) viscosity
   (b) surface tension
   (c) friction
   (d) elasticity
Ans: (b)
435. The spectrum of white light can be studied by
   (a) a microscope
   (b) a telescope
   (c) a stereoscope
   (d) a spectroscope
Ans: (d)
436. A small bubble of air deep down in a lake rises up to the top of the lake.
   The volume of the bubble on coming up will
   (a) increase
   (b) decrease
   (c) will not change
   (d) first increase and then decrease
Ans: (a)