Unit 1 - ĐCN: Electrical Materials

A material that can be melted and formed into shapes that become hard, and can then be melted again

• Thermosetting plastic material

• Conducting material

• Semiconducting material   

• Thermoplastic material

A substance, such as silicon, that allows some electricity to flow through it, used in making electronic devices:

• semiconductor         

• dielectric

• Insulator       

How many properties do the high resistivity materials have?

• 3

• 4

• 5     

• 6

The forbidden energy gap between valence and ............. band is very small.

• Empty

• Semiconducting

• Conduction

• Electrical

Soft magnetic materials have small ............ of hysteresis loop, high permeability, high saturation value, low eddy current losses which are achieved by using laminated cores, less residual magnetism.

• Large area     

• Enclosed area

• Magnetic area

• Resistant area

The conducting materials are required to be joined and the joint must have minimum contact resistance. These materials must have a good ..........

• Low temperature coefficient

• Sufficient mechanical strength     

• Ductility       

• Solderability

The material should have a high..........so that it should get oxidised when used in different environmental conditions.

• Oxidation resistance

• High melting point strength

• High mechanical  

• Low temperature coefficient

A device used to control and change the flow of electric current through a machine such as an electric light. R_______

A device used to store an electrical charge. C ________

extremely hard. A_________