Static Electricity
FILL IN THE BLANK
only ______ move or shift from one object to the next
electrons
what equation of ohms law would you use if you want to find Current
I=V/R
FILL IN THE BLANKS
in a series circuit, the loads _____ be controlled independently.
In a parallel circuit, the loads ______ be controlled indepandently
can or cannot
in a series circuit, the loads _CANNOT_ be controlled independently.
In a parallel circuit, the loads _CAN_ be controlled independently
What is the formula used to calculate power
P=W/t
True or False?
magnesium is a good insulator
FALSE
Magnesium is a metal so its a good conductor not an insulator
What are the 3 ways an object can become charged
1.charging by FRICTION
2. charging by CONTACT
3.charging by INDUCTION
what voltage is required to move 6A through 5 Ω
V=IR
V=(6A)(5Ω)
V=30V
True or false?
In a parallel circuit, if one load goes out or is switched off, the other loads still operate.
TRUE
what unit is power measured in
Watts
what is the 5 step method you use to solve word problems and what does each letter stand for
G-given
R-required
A-analysis
S-solution
P-paraphrase
The transfer of electrons between two neutral objects that occurs when they are rubbed together or come in contact is called
a. charging by friction
b. charging by contact
c. charging by induction
d. grounding
a. charging by friction
what is the current in a 160V circuit if the resistance is 2Ω
I=V/R
I=160V/2Ω
I=80A
what happens to the brightness of a lightbulb as you add more loads to a SERIES circuit
The lightbulbs dimmer each time
A device performs 12000 joules of work pulling an object for 20 seconds. What is the device's power
P=w/t
P=12000J/20s
=600W
what is the name of the atomic particle that has a positive electric charge?
what is the name of one that has a negative electric charge?
1.proton
2.electron
what are the 3 laws of electric charges
1. like charges repel
2. opposite charges attract
3. charged objects attract neutral objects
A light bulb has a resistance of 8Ω and a current of 10A. How much voltage can be applied before the bulb will break.
V=IR
V=(10A)(8Ω)
V=80V
In a series circuit,
what is the equation for current?
What about a parallel circuit?
SERIES: IT= I1 = I2 = I3...
PARALLEL: IT= I1 + I2 + I3...
The power rating of an electric lawn mower is 2000 watts. If the lawn mower is used for 120 seconds, how many joules of work can it do?
W=pxt
=(2000W)(120s)
=240000J OR 240kJ
A toaster produces 10.5 kJ of useful energy as it burns some bread. It requires 25.0 kJ to operate the toaster. How efficient is the toaster?
%Efficiency = Output Energy/Input energy x100
%Efficiency= 10.5kJ/25.0kJ x100
%Efficiency=0.42x100
%Efficiency= 42%
If there is a lightning storm
name 3 things you SHOULD do
-stay indoors
- get out of water
- stay away from open fields
- stay in a car
- stay away from trees
a walkman uses 4 standard 1.5V batteries. How much resistance is in the circuit if it uses a current of 0.02A
1.5x4= 6.0V
R=V/I
R=6.0V/0.02A
R=300Ω
in a series circuit,
the equation for total/equivalent RESISTANCE is...
what about in a parallel circuit?
SERIES: RT = R1 + R2 + R3
PARALLEL= 1/RT/EQ = 1/R1 + 1/R2 + 1/R3
A 750 watt hairdryer is used for 60 seconds. How many joules of energy are used?
W=Pxt
W = (750 W)(60 s)
W =45000J OR 45 kJ
to avoid the risks of an electrical fire, what is one device that helps stop the flow of electricity when Circuits become too hot
Fuses or circuit breakers