Natural rubber is obtained from milky sap of tropical trees

Related Mcqs:

1. Dielectric strength of rubber is around____________?

   A. 5 kV/mm
   B. 15 kV/mm
   C. 30 kV/mm
   D. 200 kV/mm

2. The relative permittivity of rubber is____________?

   A. between 2 and 3
   B. between 5 and 6
   C. between 8 and 10
   D. between 12 and 14

3. Rubber is most commonly used insulation in cables

   A. Yes
   B. No

4. The insulating material for a cable should have__________?

   A. low cost
   B. high dielectric strength
   C. high mechanical strength
   D. all of the above

5. The surge resistance of cable is__________?

   A. 5 ohms
   B. 20 ohms
   C. 50 ohms
   D. 100 ohms

6. A certain cable has an insulation of relative permittivity 4. If the insulation is replaced by one of relative permittivity 2, the capacitance of the cable will become_____________?

   A. one half
   B. double
   C. four times
   D. none of the above

7. In the cables, sheaths are used to___________?

   A. prevent the moisture from entering the cable
   B. provide enough strength
   E. provide proper insulation
   D. none of the above

8. The insulating material should have____________?

   A. low permittivity
   B. high resistivity
   C. high dielectric strength
   D. all of the above

9. The thickness of metallic shielding on cables is usually_______________?

   A. 0.04 mm
   B. 0.2 to 0.4 mm
   E. 3 to 5 mm
   D. 40 to 60 mm

10. In a cable the voltage stress is maximum at____________?

    A. sheath
    B. insulator
    E. surface of the conductor
    D. core of the conductor