Emi Ac Onemark.docx

One marks questions EMI and AC: 1. What is the SI unit of magnetic flux? 2. State Lenz’ law. 3. Write Faraday’ law with Lenz’ correction 4. What does the negative sign in the expression for induced emf e = -dΦ/dt imply? 5. How can eddy currents be minimized? 6. Define back emf 7.Why back emf is less than forward emf? 8. Mention an application of eddy currents. 9. What is the SI unit of inductance 10. Define motional emf. 11.Mention the expression for the self – inductance. 12. define coefficient of mutual inductance. 13. Mention the principle of an AC generator? 14. Mention the expression for the magnetic potential energy stored in an inductor

15. Write the relation between rms voltage and peak voltage. 16. What is the phase difference between voltage and current in a pure capacitive circuit? 17. What is wattless current? 18. What is electrical resonance? 19. Define quality factor. 20. What is power factor?