Download Example: Force F An interaction between two objects resulting in a

NAME: _______________________________
REVIEW ACTIVITY 1 FOR ELECTRICITY 1 TEST – CP (KEY)
1.
Fill in the table below:
Term
Example:
Force
What is
the
variable
name?
F
Voltage
V
Charge
I
Current
q
Resistance
R
Conceptual Definition
(use words or analogies)
What do we
measure it in?
An interaction between
two objects resulting in a
change in motion.
Newtons
Electric potential
Potential Difference
Electrical Pressure
Flow of Charge
Property of a substance
resulting in an attraction
or repulsion (+ or -)
Measure of difficulty for
charge to flow
Volts
Coulombs
Amps
Ohms
2. What is the definition of 1 volt? ____Joule/Coulomb (J/C)
3. What is the definition of 1 Amp? _____Coulomb/sec (C/s)
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4. Draw the circuit symbols for the following electrical components:
Battery
Resistor
Lamp (bulb)
Fuse
Wire
Ammeter
Open switch
Voltmeter
LED
5. Draw a circuit diagram showing two batteries and a bulb. Show the direction of the
current using arrows.
6. A good conductor has a low/high (circle one) resistance.
7. Describe the two conditions that must exist to have a current – (see Electricity Packet
notes).
1. Closed conducting path from positive terminal to negative terminal
2. Must be electric potential difference across two ends of circuit
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8. What type of current is delivered to your home? AC What type of current does a battery
provide? DC
9. What is the voltage of your outlet at home? 120 V_ What is the voltage of a D size
battery? 1.5 volts
10. Draw a light bulb (anatomy of a light bulb). Label the electrical contacts, the filament and
show all wiring inside the light bulb. What is the filament made of? __tungsten_______
11. Define the following:
Incandescence: a process where light is created from running electricity across a
filament that gets hot and glows.
Electroluminescence: a process where light is created by running electricity over semi-
conductors to excite electrons that give off light. LED lights use this process.
Fluorescence: a process where light is created by running a current through mercury
and phosphorus to create light.
Which process is least efficient in generating light in your home? incandenscence
12. Name two things that are different about the way an LED bulb lights up compared to an
incandescent light bulb.
1. Threshold voltage - there is a minimum voltage that is required for the LED to
light – not the incandescent light and 2. LEDs have a polarity which means the
current must go in through the LED one way to create light; it will not create light if
it goes the other way. We did not see this with the incandescent bulb.
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13. Using what you learned in Activity 7.2 (pink colored packet), answer the following:
a.
As the number of bulbs are added in a circuit, the bulb brightness
increases/decreases (circle one) and the current increases/decreases (circle one).
b. As the number of batteries are added in a circuit, the bulb brightness
increases/decreases (circle one) and the current increases/decreases (circle one)
14. If the distance between two positive charges is doubled, how will the force between them
change? 4 x less (1/4 original force) Use a drawing to explain the change showing the
force vectors.
BEFORE:
AFTER:
Force and distance have an inverse square relationship. If the distance is doubled, the force
decreases by 4 times.
15. Two charges exert an attractive force. If one of the charges doubles, how will the force
between them change?Twice as great (2x more) Use a drawing to explain the change
showing the force vectors:
BEFORE:
AFTER:
Force and charge have a direct relationship. If the charge is doubled, the force is
doubled.
What is the name of the law that tells us the relationship between the electric force and the
distance between charges?______Coulomb’s Law_____
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