A. minimum
B. maximum
C. nil
D. none of the above
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Related Mcqs:
- The cold rolled grain oriented steel has _________ permeability in the direction of the grain orientation?
- A. minimum B. maximum C. nil D. none of the above...
- For 275 kV transformers, using cold rolled grain oriented steel, which of the following values of flux density may be used?
- A. 1.0 Wb/m2 B. 1.1 Wb/m2 C. 1.3 Wb/m2 D. 1.6 Wb/m2 E. None of the above...
- Hot rolled sheets have ___________ value of permeability?
- A. zero B. low C. high D. none of the above...
- In transformers using hot rolled steel, the cross-section of the yoke is made about __________ greater than that of the core?
- A. 5 percent B. 10 percent C. 15 percent D. 30 percent E. none of the above...
- The usual values of maximum flux densities for distribution transformers using hot rolled silicon steel are______________?
- A. 0.5 to 0.8 Wb/m2 B. 0.8 to 1.0 Wb/m2 C. 1.1 to 1.35 Wb/m2 D. 1.4 to 1.8 Wb/m2...
- __________ has a low relative permeability and is used principally in field frames when cost is of primary importance and extra weight is not objectionable?
- A. Cast steel B. Aluminium C. Soft steel D. Cast iron...
- The noise produced by a ___________ cooled machine is less as the rotor moves in a medium of smaller density?
- A. air B. hydrogen C. either A. or B. D. none of the above...
- In self cooled motors the cooling time constant is about ___________ than the heating time constant because cooling conditions are worse at standstill?
- A. 2 to 3 times greater B. 3 to 4 times greater C. 4 to 5 times greater D. none of the above...
- The laminations of the armature of a D.C. machine are usually ___________ thick?
- A. 0.1 to 0.2 mm B. 0.2 to 0.3 mm C. 0.3 to 0.4 mm D. 0.4 to 0.5 mm...
- ___________ brushes are fragile and cause excessive wear of commutator?
- A. Natural graphite B. Hard carbon C. Electro graphitic D. Metal graphite...
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