Say if the following statements are true or false. If the statement is false
and explain why:
1) A motor puts an object in rotation around a fixed axis, applying force perpendicular to the axis.
2) Centripetal acceleration is used to separate substances of greater and lesser density.
3) The ultracentrifuge, devised in the 1883 by the Swedish chemist Theodor Svedberg, found wide application in scientific research.
4) A mechanical method of separating immiscible liquids or solids from liquids by the application of gravity force.
5) Tensile stress in the cylinder wall limits the centrifugal force which can be generated in a unit of a given size and material of construction.
6) There are two major types of centrifuges: sedimenters and filters.
7) A filtering centrifuge contains a solid-wall cylinder or cone rotating about a horizontal or vertical axis.
8) In filtering centrifuge the filtration rate increases with the centrifugal force and with the permeability of the solid cake.
9) If the material to be processed has low residual impurities and a high washing requirement, the greater flexibility of the batch process allows the necessary adjustments.
10) Centrifugal processing provides a number of unique advantages.
8. Choose the correct continuation to complete the following statements:
1) Centrifugal force is generated inside
a) a cylindrical-conical chamber
b) stationary equipment
2) Very high forces can be developed only in
a) very small centrifuges.
b) mechanically driven bowls
3) A sedimenting centrifuge contains
a) a solid-wall cylinder
b) filters
4) A filtering centrifuge operates on the same principle as
a) the spinner
b) a household washing machine.
5) The amount of liquid adhering to the solids after they have been spun depends on
a) the permeability of the cake
b) the centrifugal force applied
6) Materials of 45 microns and above that are relatively incompressible are highly suitable for
a) separation by sedimentation techniques.
b) separation by filtration.
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