Indicate which of the following material does not retain magnetism permanently
Correct answer: A. Soft iron
- A. Soft iron
- B. Stainless steel
- C. Hardened steel
- D. None of the above
Explanation
Soft iron has low retentivity, so its magnetism disappears nearly completely when the magnetising field is removed. Hardened steel is commonly used for permanent magnets because it retains magnetism strongly.
Last updated
Practise Electrical Machines
1,061 free Electrical Machines MCQs from Electrical Engineering, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Electrical Engineering questions like this
Electrical Engineering is on 2 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
5 H.P., 50-Hz, 3-phase, 440 V, induction motors are available for the following r.p.m. Which motor will be the costliest ?
A 220 V D.C. generator is run at full speed without any excitation. The open circuit voltage will be_____________?
A 3-phase 440 V, 50 Hz induction motor has 4% slip. The frequency of rotor e.m.f. will be____________?
A 3-phase induction motor delta connected is carrying too heavy load and one of its fuses blows out. Then the motor______________?
A 3-phase induction motor stator delta connected, is carrying full load and one of its fuses blows out. Then the motor_______________?