# Home / EEE / Magnetism and Electromagnetism :: General Questions

### EEE :: Magnetism and Electromagnetism

1. When the speed at which a conductor is moved through a magnetic field is increased, the induced voltage

2.  A. increases B. decreases C. remains constant D. reaches zero   3. The induced voltage across a coil with 250 turns that is located in a magnetic field that is changing at a rate of 8 Wb/s is

4.  A. 1,000 V B. 2,000 V C. 31.25 V D. 3,125 V   5. For a given wirewound core, an increase in current through the coil

6.  A. reverses the flux lines B. decreases the flux density C. increases the flux density D. causes no change in flux density   7. If the cross-sectional area of a magnetic field increases, but the flux remains the same, the flux density

8.  A. increases B. decreases C. remains the same D. doubles   9. When the current through the coil of an electromagnet reverses, the

10.  A. direction of the magnetic field reverses B. direction of the magnetic field remains unchanged C. magnetic field expands D. magnetic field collapses   11. What is the reluctance of a material that has a length of 0.07 m, a cross-sectional area of 0.014 m2, and a permeability of 4,500 Wb/At × m?

12.  A. 1111 At/Wb B. 111 At/Wb C. 11 At/Wb D. 1 At/Wb   13. A coil of wire is placed in a changing magnetic field. If the number of turns in the coil is decreased, the voltage induced across the coil will

14.  A. increase B. decrease C. remain constant D. be excessive   15. What is the flux density when the flux is 5.5 Wb and the cross-sectional area is 6 × 10–3 m2?

16.  A. 91.7 T B. 917 T C. 91 T D. 9.7 T   17. The unit for reluctance is

18.  A. tesla B. At/Wb C. At/m D. Wb   19. If the steel disk in a crankshaft position sensor has stopped with the tab in the magnet's air gap, the induced voltage

20.  A. increases B. decreases C. is zero D. will remain constant   