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Electricity Test Review
Name _________________________________________
Date _________________
Class _________________
Directions: In the blank, write the term that best completes each statement.
1. The accumulation of excess electric charge on an object is called
STATIC ELECTRICITY
2. A material in which electrons are able to move is a(n) CONDUCTOR.
3. Transferring charge by touching or rubbing is called CONDUCTION.
4. The net movement of electric charges in a single direction is called electric
CURRENT.
5. Voltage difference is measured in VOLTS.
6. A closed path that electric current follows is a(n) CIRCUIT.
7. Resistance is the tendency of a material to SLOW the flow of electrons.
8. There are TWO types of electric charge.
9. Protons have POSITIVE charge.
10. Electrons have NEGATIVE charge.
11. All atoms are held together by ELECTRICAL forces.
12. The best electrical conductors are METAL.
13. Electric wires are usually made of COPPER.
14. A(n) ________________________ is a transfer of charge between two objects because of a
buildup of static electricity.
15. Connecting an object to Earth with a conductor is called GROUNDING.
16. Rubber and glass are examples of INSULATORS, which do not allow electrons to
flow easily.
17. Electric current is measured in AMPERES.
18. According to Ohm’s law, as the resistance in a circuit _______, the current _________.
a. increases, remains constant
b. decreases, decreases
c. increases, increases
D. INCREASES, DECREASES
19. Lightning is ______.
A. VERY LARGE DISCHARGE OF STATIC ELECTRICITY
b. a buildup of neutrons
c. a low voltage electric current.
d. harmless.
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Electricity Test Review
Name _________________________________________
Date _________________
Class _________________
II. Understanding Concepts
Skill: Observing and Inferring
Directions: Use the diagrams to answer the following question.
Figure 1
Figure 2
1. What inference can you make about the electrical condition of the combs in Figures 1 and 2?
The comb in figure 1 is negatively charged attracting the protons in the metal and causing electrons
to move aggressively away from the comb causing the leaves to raise. The comb in figure 2 is not
charged
2. What is the general composition of a battery? Draw a picture to illustrate.
Two electrodes (a positive cathode and a negative anode) and an electrolyte which allows for
a barrier for electrons to flow.
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Electricity Test Review
Name _________________________________________
Date _________________
Class _________________
III. Applying Concepts
Writing Skills
Directions: Answer the following questions on the lines provided.
Reason How can a charged comb cause your hair to rise when it isn’t even touching your
head? Through the process called induction which only requires objects to come into close proximity
of each other.
IV. Solving Problems
1. The current through a 5-ohm resistor connected to a 150-V power supply is
I = V/R
I = 150v/ 5 ohms (Ω)
I = 30 amps (A)
2. What is the resistance of a toaster that uses 5 A of current when connected to a 120-volt power source?
R = V/I
R = 120v/ 5A
R = 40 Ω
3.If you accidentally grabbed the prongs of a partially plugged-in 120-V electrical plug on a day when your
skin resistance was 130,000 ohms, how much current would pass through your body?
I = V/R
I = 120v/ 130,000 ohms (Ω)
I = 0.0009 amps (A)
4. How much power is used by a 12.0-V car battery that draws 0.5 A of current?
P=VxI
P = 12.0v x 0.5A P = 24 watts (W)
5. When plugged into a 120-V wall outlet, how much current is used by an electric blanket rated at 140 W?
I = P/V
I = 140 W/ 120v
I = 1.17 A
6. A 120-watt light bulb is connected to a 120-V outlet. How much current is in the light bulb?
I = P/V
I = 120 W/ 120v
I = 1.0 A
7. A light bulb is plugged into a 120-volt outlet and has a 0.7 A current in it. What is the power rating of the
light bulb?
P=VxI
P = 120v x 0.7A
P = 84 watts (W)
Chapter Resources • Electricity
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Electricity Test Review
Name _________________________________________
Date _________________
Class _________________
V. Diagrams
Draw a series circuit with one battery, one switch, two bulbs and one resistor
Light bulb
Battery
Resistor
Switch
Draw a parallel circuit with one battery, one switch, three bulbs and one voltmeter
Voltmeter
Which light bulbs will light?
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