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Date Due:
Electricity &
Magnetism
Physical Science
Chapter 7
Name:
Electricity
1.
Define the following terms:
a. electric charge=
b.
electric force=
c.
static electricity=
d.
conduction=
e.
induction=
f.
static discharge=
g.
electric current=
h.
ampere=
i.
direct current=
j.
alternating current=
k.
electric potential energy=
l.
voltage=
m. electrical conductor=
n.
electrical insulator=
o.
resistance=
2.
What makes up positive charge?
3.
What makes up negative charge?
4.
What happens to an atom if it loses an electron?
5.
What produces a net electric charge?
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6.
What is the unit for electric charge?
7.
How do like charges behave?
8.
How do opposite charges behave?
9.
What is the relationship of electric forces between two objects?
10. What does the strength of the electric field depend on?
11. What does an electric field exert forces on?
12. What does the force depend on?
13. What causes a greater force?
14. How can charger be transferred?
15. What is the law of conservation of charge?
16. When does static discharge occur?
17. What are the two types of electric current?
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18. Where do you find direct current?
19. Where do you find alternating current?
20. What is Ohm’s Law?
21. What affects resistance?
22. What is necessary for charge to flow?
23. What materials make good conductors?
24. What materials make good insulators?
25. Is the following true or false? Metals are good conductors because they do not have freely moving
electrons.
Match each material to the category of conductor or insulator.
a. Conductor
b. Insulator
26. Copper
27. Plastics
28. Rubber
29. Silver
30. Wood
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Name:
Magnetism
31. Define the following terms:
a.
magnetism=
b.
magnet=
c.
poles=
d.
magnetic force=
e.
magnetic field=
32. What are the two types of magnetic poles?
33. How do magnetic poles interact with each other?
34. Circle the letter of each sentence that is true about magnetic force.
a.
Two magnets that approach each other may attract or repel.
b.
Magnets forces do not vary with distance.
c.
Opposite magnetic poles repel each other.
d.
Magnetic forces act over a distance.
35. Where is a magnetic field strongest?
36. How are the lines in the magnetic field drawn?
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Name:
37. Why is the Earth a magnet?
38. Is the following sentence true or false? Magnetic force can be exerted on moving charges, as well as on
iron or on anther magnet.
39. Circle the letter of each sentence that is true about magnetic field.
a.
Magnetic fields surround a magnet and can extend toward the north pole.
b.
Field lines begin near the south pole of a magnet and extend toward the north pole.
c.
Iron filings are most attracted to areas where the field is strongest.
d.
A magnetic field is strongest near the north and south poles of a magnet.
40. Complete the concept map.
Properties
of Magnets
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Name:
Electromagnetism
41. Define the following terms:
a. Electromagnetism=
b. electromagnetic force=
c. electromagnetic wave=
d. solenoid=
e. electromagnet=
f. electromagnet induction=
g. Faraday’s law=
h. generator=
i. transformer=
42. What causes the electromagnetic force?
43. What creates a magnetic field?
44. What happens when current is changed?
45. What happens when a magnet is moved in and out of a coil?
46. What are the two types of magnetic poles?
47. Circle the letter of each sentence that is true about electromagnets.
a.
Placing an iron rod in a solenoid reduces the strength of its magnetic field.
b.
Devices that utilize electromagnets include doorbells and telephones.
c.
A magnetic field can be turned on and off with an electromagnet.
d.
An electromagnet can control the direction of a magnetic field.
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48. Why must we transform electrical energy so homes can use it?
49. Why do transformers only use alternating current?
50. How do transformers work?
51. How does a transformer change voltage and current?
52. Are the following sentences true or false?
a.
Moving electric charges create a magnetic field.
b.
The vibrating charges that produce an electromagnetic wave also create a magnetic field.
c.
The strength of the magnetic field through the center of a coil of current-carrying wire is calculated
by adding together the fields from each turn of the coil.
d.
Decreasing the current to the solenoid decreases the strength of an electromagnet.
53. Use the formula to calculate output voltage.
A step-up transformer has a primary coil with 500 turns of wire, and a secondary coil with 50 turns. If the
input voltage is 120 V, what is the output voltage?
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