1) What type of fibres are orlon and terylene? Give two properties and uses of each. 2) Give two advantages and disadvantages of synthetic fibres.
3) Write three differences between thermoplastic and thermosetting polymers.
4) What is polythene? Give two characteristics of it.
5) What type of polymer is polystyrene? Give its two uses.
6) Give two applications each of teflon and bakelite,
7) What is araldite? Write its uses.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia