Q. 1. What is a magnetic fields?
Q. 2. What are the magnetic lines of force?
Q. 3. What is an electric motor?
Q. 4. What is a solenoid?
Q. 5. Which effect of electric current is untilized in the working of an electric motor?
Q. 6. What is the frequency for a.c (altemating current) in india?
Q. 7. On what principle is an a.c generator based?
Q. 8. Why don’t two magnetic lines of force interest each other?
Q. 9. Name some source of direct current?
Q. 10. When does an electric short circuit occur?
Q. 11. What is the usual colour code followed for connecting ive, neutral and earth wires. Why is it so important?
Q. 12. What is electromagnetic inductions?
Q. 13. State the rule to determine the direction of magnetic field produced around a current carrying conductor?
Q. 14. What is the role of a fuse in the electric circuits?
Q. 15. Explain direct and alternating current?
Q. 16. What is the function of an earth wire? Why is it necessary to earth metallic appliances?
Q. 17. Draw magnetic field lines around a bar magnet?
Q. 18. Why does a compass needle get deflected brought near a bar magnet?
Q. 19. List the properties of magnetic lines of force?
Q. 20. What is the principle of an electric motor?
Q. 21. State the principle of an electric generator.
Q. 22. Two circular coils a and b are placed closed to each other. If the current in coil a is changed, will some current be induced in the coil b? Give reason.
