What are the materials used for brushes in dc machines?a.Steelb.Aluminiumc.Irond.Carbon

What is the function of the brushes in a DC machine?a.To conduct current to and from the armature windingsb.To provide mechanical support to the rotorc.To control the speed of the machined.To convert mechanical energy to electrical energy

1. L_ _ _ is a very heavy, soft, dark grey poisonous metal, usually in the center of pencils. 2. The machines should be made of ­­­d_ _ _ _ _ _ materials so that they can be used for a long time. 3. Iron is a r_ _ _ _ metal that is used to make steel so it's hard to bend. 4. Copper is used for wire because it is more d_ _ _ _ _ _ than most other metals. 5. The pipe needs to bend several times as we pass it into the structure, so we don’t want it to be stiff. We should choose a f_ _ _ _ _ _ _ pipe. 6. Glass which is a b_ _ _ _ _ _ material used in the production of our mobile phones may break if the phone is dropped. 7. High temperature super alloys are used in applications requiring material that can w_ _ _ _ _ _ _ _ extreme forces and severe oxidizing. 8. T_ _ _ _ _ _ _ is a chemical element that is a light, strong, white metal. Its symbol is Ti. 9. Copper can be mixed with tin and led to produce b_ _ _ _ _. 10. T_ _ _ _ _ _ _ _ _ _ _ _ _ can be melted and formed into shapes that become hard, and can then be melted again.

Discuss the various magnetic and mechanical properties of materials with examples.

II    Explain and differentiate the properties and uses of the following materials:a.    Goldb.    Copperc.     Silverd.    Tungstene.    Siliconf.     Nickelg.    Tinh.     Asbestos i.    Titanium  j.   Plastics

Which of the following is NOT a typical application of industrial robots?WeldingAssemblyHealthcarePainting