MAGNETIC EFFECTS OF ELECTRIC CURRENT
1. State the effects of current.
2. Why does a compass needle placed near a current carrying wire show deflection?
3. How can the magnetic field produced around a current carrying conductor be detected?
4. Give one example each of the following:- (a) magnetic effect of electric current (b) electric effect of moving magnets
5. Define magnetic field.
6. Give the characteristics of magnetic field lines.
7. With the help of an activity show how magnetic field lines around a bar magnet can be obtained. Also draw the pattern of
magnetic field lines around a bar magnet.
8. How is the deflection in the compass needle affected as we move it along a field line (a) towards the poles (b) away from
poles.
9. State the factors on which strength of magnetic field due to a straight current carrying conductor depends.
10. “the concentric circles representing the magnetic field around a current carrying straight wire become larger and larger as
we move away from it.” What conclusion can be drawn from this statement?
11. Name and state the rule to determine the direction of magnetic field produced around a current carrying conductor.
12. Two magnetic lines of force do not intersect each other. Why?
13. Draw the pattern of lines of force due to a magnetic field through and around a current carrying loop of wire. How does the
strength of magnetic field produced at the centre of the loop be affected if:-
(a) strength of the current passing through it is doubled?
(b) the radius of the loop is reduced to half the original value?
(c) the radius of the loop is doubled its original value and at the same time current passing through it is also doubled?
14. What does the arrow of the magnetic field line indicate?
15. What does crowding of field lines at a point mean?
16. Will a circular loop of bigger radius produce higher magnetic field than a loop of smaller radius if current flowing though
both the loops is same? Give reason.
17. What is a solenoid?
18. Draw comparison of magnetic field pattern due to current carrying solenoid and that of a bar magnet.
19. The field lines inside the solenoid are in the form of parallel straight lines. What does this indicate?
20. What is an electromagnet?
21. How can we magnetise a piece of magnetic material?
22. Show with the help of an activity that a force is exerted on the current carrying conductor when ti is placed in a magnetic
field.
23. State the rule which is used to find the direction of force exerted on a current carrying conductor when placed in a magnetic
field.
24. A charged particle experiences minimum force when it travels-
(a) parallel to the magnetic field (b) normal to the magnetic field
(c) at 450 to the field (d) at 750 to the field.
25. The magnetic field due to a long straight conductor carrying current is independent of
(a) the current (b) distance of the conductor from the point (c) length of the conductor (d) none
26. Give a few applications / uses of electromagnets in daily life.
27. What is electromagnetic induction?
28. State the rule which is used to find the direction of induced current.
29. How can current be induced in a coil? (State different ways of inducing current in a coil)
30. A bar magnet is moved towards a solenoid whose ends are connected to a galvanometer? State your observations and give
reason for the same.
31. Give the energy transformation taking place in a (a) generator (b) electric motor
2
32. In India, what is the p.d. between neutral and live wire?
33. What is the current rating for (i) circuit consisting of bulbs, fans in the household (ii) circuit used for air conditioners,
geysers?
34. State the colour of insulation used for – live wire, earth wire, neutral wire; used in the household circuit?
35. Give the function of ‘earth wire’?
36. What is (i) overloading (ii) short circuiting?
37. How is the household circuit protected from damage due to sudden hike in supply voltage?
38. Direction of current (a.c.) changes after every 1/100 second. What is its frequency?
39. Give the difference between a.c. and d.c.
40. Give one advantage of a.c. over d.c.
41. Differentiate between an electromagnet and an ordinary bar magnet.
42. Name one material in each case which is used to make a (i) permanent magnet (ii) temporary magnet
1. State the effects of current.
2. Why does a compass needle placed near a current carrying wire show deflection?
3. How can the magnetic field produced around a current carrying conductor be detected?
4. Give one example each of the following:- (a) magnetic effect of electric current (b) electric effect of moving magnets
5. Define magnetic field.
6. Give the characteristics of magnetic field lines.
7. With the help of an activity show how magnetic field lines around a bar magnet can be obtained. Also draw the pattern of
magnetic field lines around a bar magnet.
8. How is the deflection in the compass needle affected as we move it along a field line (a) towards the poles (b) away from
poles.
9. State the factors on which strength of magnetic field due to a straight current carrying conductor depends.
10. “the concentric circles representing the magnetic field around a current carrying straight wire become larger and larger as
we move away from it.” What conclusion can be drawn from this statement?
11. Name and state the rule to determine the direction of magnetic field produced around a current carrying conductor.
12. Two magnetic lines of force do not intersect each other. Why?
13. Draw the pattern of lines of force due to a magnetic field through and around a current carrying loop of wire. How does the
strength of magnetic field produced at the centre of the loop be affected if:-
(a) strength of the current passing through it is doubled?
(b) the radius of the loop is reduced to half the original value?
(c) the radius of the loop is doubled its original value and at the same time current passing through it is also doubled?
14. What does the arrow of the magnetic field line indicate?
15. What does crowding of field lines at a point mean?
16. Will a circular loop of bigger radius produce higher magnetic field than a loop of smaller radius if current flowing though
both the loops is same? Give reason.
17. What is a solenoid?
18. Draw comparison of magnetic field pattern due to current carrying solenoid and that of a bar magnet.
19. The field lines inside the solenoid are in the form of parallel straight lines. What does this indicate?
20. What is an electromagnet?
21. How can we magnetise a piece of magnetic material?
22. Show with the help of an activity that a force is exerted on the current carrying conductor when ti is placed in a magnetic
field.
23. State the rule which is used to find the direction of force exerted on a current carrying conductor when placed in a magnetic
field.
24. A charged particle experiences minimum force when it travels-
(a) parallel to the magnetic field (b) normal to the magnetic field
(c) at 450 to the field (d) at 750 to the field.
25. The magnetic field due to a long straight conductor carrying current is independent of
(a) the current (b) distance of the conductor from the point (c) length of the conductor (d) none
26. Give a few applications / uses of electromagnets in daily life.
27. What is electromagnetic induction?
28. State the rule which is used to find the direction of induced current.
29. How can current be induced in a coil? (State different ways of inducing current in a coil)
30. A bar magnet is moved towards a solenoid whose ends are connected to a galvanometer? State your observations and give
reason for the same.
31. Give the energy transformation taking place in a (a) generator (b) electric motor
2
32. In India, what is the p.d. between neutral and live wire?
33. What is the current rating for (i) circuit consisting of bulbs, fans in the household (ii) circuit used for air conditioners,
geysers?
34. State the colour of insulation used for – live wire, earth wire, neutral wire; used in the household circuit?
35. Give the function of ‘earth wire’?
36. What is (i) overloading (ii) short circuiting?
37. How is the household circuit protected from damage due to sudden hike in supply voltage?
38. Direction of current (a.c.) changes after every 1/100 second. What is its frequency?
39. Give the difference between a.c. and d.c.
40. Give one advantage of a.c. over d.c.
41. Differentiate between an electromagnet and an ordinary bar magnet.
42. Name one material in each case which is used to make a (i) permanent magnet (ii) temporary magnet