Question

*When should you not use plastics?

a) when they are exposed to ultra-violet radiation.

b) when they are loaded in uniaxial tension.

c) when they are exposed to high voltages.

d) when they must deform plastically.

e) None above.

*what is a polymeric material?

a.it is a material that shows many different allotropes depending on conditions of temperature and pressure.

b. it is a material that has polybonds holding its atoms to form solid.

c. it is a material that contains many chemically bounded units that are themselves bounded together to form a solid.

d. it is a material that shows elastic behavior at high temperatures and polymetric behavior at low temperature.

e. non of above

Answer 1

or plastie o m When polymers de exposed to Un light radiation then polymers are auttacked by uv light and products using these material may epack or disintegrate. So, these Plastie can excite photous and create radical which are harmful. So, @ when they are exposed to UV radiation is correct answer. ENNE 0 0 Molecular weight of polymer is very high ( 7, 1000) Polymers are made by so many no of monomer unit. All the synthetic polymers are organic compounds and are derived from petroleum fraction on natural gas or coal. Molecules of polymer are to Very long , Chain like and of high molecular Weights. So @ It is a material that contains many Chemically bounded anits that are themselves bounded together to form a solid is correct answer.