Vocabulary Review
__________________ 1. A long coil of wire that contains many loops is called a(n) _____.
__________________ 2. A group of neighboring atoms whose electrons’ magnetic fields all align in the
same direction is called a(n) _____.
__________________3. The ______ can be used to determine the direction of a field produced by an electromagnet relative to the flow of a conventional current.
__________________ 4. A(n) _______ is a device that converts electrical energy into rotational kinetic
energy.
__________________ 5. A(n) _______ is a device that converts rotational kinetic energy into electrical
energy.
__________________ 6. A magnet created when a current flows through a coil of wire is a(n) _____.
__________________7. A magnet is ___________, which means it has two distinct and opposite ends.
__________________ 8. Is the process in which current is generated in a wire due to the relative motion
between the wire and a magnetic field.
S 9.
Draw the domains for the following material a. Magnetic b. Nonmagnetic c. Iron inside a solenoid d. Magnet near iron N
10. Draw the field lines through and around the bar magnet shown below:
S N
11. What can you say about the relationship between the domains and field lines in a permanent magnet?______________________________________________________________________________
_____________________________________________________________________________________

Right Hand Rule
12. Your thumb always points in the direction of the ___________________________.
13. Your fingers always point in the direction of the ____________________________.
14. What does an “X” stand for on the page? __________________________________
15. What does a dot stand for on the page? ___________________________________
16. Draw the field lines for the following wire configurations a.
I b. c.
I
I
Transformer Practice (show your work in the provided area)
17. The primary coil in a transformer has 76 loops and the secondary coil has 580 loops. The incoming primary voltage and current are 1250 V and 15.0 A. a. What type of transformer is this? __________ b. What is the secondary power? _______ c. What is the secondary voltage? _______ d. What is the secondary current? _______
18. The primary coil in a transformer has 1870 loops. The incoming primary voltage and current are
25000 V and 0.80 A. The outgoing secondary voltage is 4545 V. a. What type of transformer is this? __________ b. What is the secondary power? _______ c. What is the secondary number of coil loops? _______ d. What is the secondary current? _______

Multiple Choice
19. The magnitude of the current in a wire is _____ to the magnetic field around the wire. a.
Proportional b.
Inversely proportional c.
d.
Unrelated
Parallel
20. Increasing the number of loops in an electromagnet causes the strength of the magnetic field to ___. a.
Increase b.
Decrease
21. The two coils of a transformer MUST _____. c.
Remain the same a.
be electrically insulated from each other b.
be wound around different iron cores c.
d.
have the same number of windings have the same resistance
22. Transformers can change _____ with relatively little loss of energy. a.
Magnetic fields b.
Power c.
Resistances d.
Voltages
23. In an ideal transformer, the electric power delivered to the secondary circuit is _____ the power supplied to the primary circuit a.
b.
Double
Equal to
Short Answer c.
Greater than d.
Less than
24. Why do opposite poles of a magnet attract and similar magnetic poles repel?
25. Why does either pole of a magnet always attract a conductor?
26. How does a solenoid induce a magnetic field in a piece of iron to create an electromagnet?

27. What was the purpose of the commutator disc in the lab?
28. What was the purpose of the electromagnet in the lab?
29. Would the rotor have spun without the commutator disc? Explain.
30. What is the difference between alternating and direct current?
31. Why does a transformer need alternating current to function properly?
32. When would you want to use direct current rather than alternating current?
33. Why do we use alternating current in power lines? You should have several reasons.