(Important Questions) Important Question For CBSE Class X Science Board Examination 2009-10 (Set -7)

Magnetic effects of current

Q. 1. Name two important properties of a magnet.

Q. 2. What is the direction of magnetic field lines inside a magnet.

Q. 3. Draw magnetic field lines to depict uniform magnetic field

Q. 4. What type of magnetic field lines represent uniform magnetic field?

Q. 5. What is the conclusion drawn by Oersted in his experiment?

Q. 6. What is the form of magnetic field lines due to a straight current carrying conductor?

Q. 7. Name the rule used to find the direction of magnetic field due to a straight current carrying conductor.?

Q. 8. How do we determine the direction of magnetic field at a point due to a given source.

Q. 9. Name the unit of magnitude of magnetic field

Q. 10. What is a solenoid?

Q. 11. What for do we apply clock rule(end rule)?

Q. 12. What is the effect of inserting a soft iron core inside a current carrying solenoid?

Q. 13. What type of core is used to make an electromagnet?

Q. 14. What are permanent magnets made of?

Q. 15. Why is soft iron not used for making a permanent magnet?

Q. 16. Name the rule to find the direction of force on a current carrying conductor placed in a magnetic field?

Q. 17. What is the condition for getting maximum force on a current carrying conductor placed in a magnetic field?

Q. 18. What happens to the force on a current carrying conductor when placed perpendicular in uniform magnetic field has its length doubled?

Q. 19. If current flowing through a conductor placed in magnetic field is halved( which is at right angles to each other)does it affect its deflection?

Q. 20. what is electromagnetic induction?

Q. 21. Name and state the rule which gives the direction of induced current?

Q. 22. Name the device which converts mechanical energy into electrical energy and vice versa?

Q. 23. Name the component used in motor which enhances the power of it and describe the component.

Q. 24. What type of current is given by a cell?

Q. 25. What type of current is used in household supply?

Q. 26. Write any two difference between A.c and D.C

Q. 27. Write one main advantage of A.C over D.C

Q. 28. Of what substance is a fuse wire made of ?

Q. 29. Where do we connect a fuse with live wire or with neutral wire/

Q. 30. What are the colors of live, neutral and earth wires?

Q. 31. What is short circuiting and overloading?

Q. 32. A current through a horizontal powerline flows in east to west direction. What is the direction of magnetic field at a point directly below it and a t a pont directly above it?

Q. 33. state two ways by which the strength of an electromagnet can be increased.

Q. 34. On what factors does the magnitude of magnetic field due to current carrying straight wire depend on?

Q. 35. state two ways by which the speed of rotation of an electric motor can be increased?

Q. 36. What are the three ways of producing inducing current

Q. 37. How can you increase the magnitude of induced current produced due to relative motion of magnet and the coil?

Q. 38. what will be the frequency of an A.C current if its direction changes after every a)0.01s? b) 0.02s

Q. 39. How will the magnetic field intensity at the centre of a circular coil carrying current change, if the current through the coil is doubled /

Q. 40. determine the polarity of the solenoid from the fig.

Q. 41. give the direction of induced current in the wire loop when the magnet moves forward as shown in fig.

Q. 42. An electron beam is moving vertically upwards. If it passes through a magnetic field which is directed from south to north in a horizontal plane, then in which direction will the beam be deflected?

Q. 43. The magnetic force acts on a moving proton is towards north in a horizontal plane.If the proton is moving vertically up, then what will be the direction of magnetic field?

Q. 44. A charged particle moves in a clockwise direction in a magnetic field which is perpendicular to plane of paper directed downward. What is the nature of charge particle.

Q. 45. A constant current is flowing through a primary coil , What will be the direction of induced current in the secondary coil placed along coaxially? Justify.

Q. 46. The magnetic field all points well inside a long straight solenoid carrying current is -------------------------

Q. 47. Draw magnetic field lines around a bar magnet

Q. 48. Give the characteristics of magnetic field lines

Q. 49. what is a compass needle?

Q. 50. What is the current rating of a) bulbs b) geysers