Electromagnetism

Electromagnetism - Introduction

1. Materials that can be attracted by a magnet are called _____ materials. A. magnet attractable B.magnet attachable

C.ferromagnetic D.magnet

2. Which of the followings are ferromagnetic materials? A.Zinc B.Nickel

C.Aluminium D.Tin

3. Which of the following materials cannot be attracted by a magnet? A.Iron B.Cobalt

C.Steel D.Copper

4. In the figure above, which diagrams show the correct magnetic field at the north or south pole of a bar magnet? A.P and S B.R and Q C.P and Q D.R and S

5. In the diagram above, which compasses show the correct direction of the magnetic field of a bar magnet? A.P, U and S B.Q, R and T C.U, R and S D.None of the above are correct

6. Which of the following diagrams shows the correct magnetic field pattern produced by the current in a straight wire? A.and R only B.R and S only C.Q, R and S only D.Q and S only

7. Which of the picture in the diagram shows a correct method in finding the direction of the magnetic field produced by a straight wire? A.P B.Q

C.R D.S

8. Which of the following statements are TRUE about the magnetic field generated by a straight current carrying conductor? I. The magnetic field strength increase when the current increases. II. The magnetic field strength increase when the distance from the conductor increases. III. The direction of the field line depends on the direction of the current. IV. The direction of the field can be determined by Maxwell's Screw Rule. A.I, II and III only B.I and III only

C.I, III and IV only D.I, II, III and IV

9. Which of the following materials is most likely to be used for the coil of an electromagnet? A.Copper B.Steel

C.Iron D.Silver

10. Which of the following materials is most likely to be used for the core of an electromagnet? A.Copper B.Steel

C.Iron D.Silver

11. Why iron is suitable to become a core of an electromagnet? I. because it is easily to be magnetized. II. because it is easily to be demagnetized. III. because it is a good conductor. IV. because it is a ferromagnetic material. A.I and III only C.I, II and IV only B.I, II and III only D.III and IV only

12. Which diagram shows the magnetic field pattern associated with a solenoid carrying a current in the direction indicated? A.P and S only B.Q and R only

C.P only D.Q only

13. The figure shows a picture of solenoid. State the magnetic pole at X when the switch is closed. A.North B.South C.Can be North or South, depends on the material of the core.