1. Chapter 28 Magnetic Fields
In this chapter we will cover the following topics:
Magnetic field vector Magnetic force on a moving charge Magnetic field lines Motion of a moving charge particle in a uniform magnetic field Magnetic force on a current carrying wire Magnetic torque on a wire loop Magnetic dipole, magnetic dipole moment Hall effect Cyclotron particle accelerator
(28 – 1)

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3. What is the equivalent resistance between points F and G
What is the equivalent resistance between points F and G? Each Resistor is 8 Ω.
(A) 2.5 Ω
(B) 5.0 Ω
(C) 2.0 Ω
(D) 4.0 Ω
(E) none of these

4. (28 – 2)

5. (28 – 3)

6. (28 – 4)

7. (28 – 5)

8. P
magnetic field line
magnetic field lines P Q
(28 – 6)

9. (28 – 7)

10. Cathode
Anode
(28 – 8)

11. .
electron C r
(28 – 9)

12. (28 – 10)

13. (28 – 11)

14. (28 – 12) . i

15. C
Top view
Side view
(28 – 13)

16. (28 – 14)

17. L R
(28 – 15)

18. L R
(28 – 16)

19. (28 – 17)

20. Two isolated conducting spheres are separated by a large distance
Two isolated conducting spheres are separated by a large distance. Sphere 1 has a radius of R and an initial charge 2Q
while sphere 2 has a radius of 3R and an initial charge 8Q. A very thin copper wire is now connected to the spheres.
Charge flows between the spheres until they reach the same electrical potential. How much charge will be transferred
from sphere 2 to sphere 1? (Note that the charge transferred can be positive, negative or zero .)
(1) Q/2 (2) 2Q (3) –Q/3 (4) -3Q (5) None of these

21. hitt The current in the 5.0 Ω resistor in the circuit shown is:
0.42A (2) 0.67A (3) 1.5A (4) 2.4A (5) 3.0A
See the figure in problem 8, exam II, Sum 07

22. Hitt
Four identical light bulbs A, B, C and D are connected in series to a constant voltage source. A wire is then connected
across B. What is the brightness of A relative to its former brightness?
(1) (2) 2.25 (3) (4) (5) none of these