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Electricity
Being Ec”Static”
Staying Current
Circuit Training
By the numbers
1 1 1 1
2 2 2 2
3 3 3 3
4 4 4 4
BEING EC’STATIC’ 1
• What is better at generating a static charge via the friction method? A conductor or an insulator? Why?
BEING EC’STATIC’ 1
• An insulator: Insulators don’t let the charge flow off the object during the rubbing that occurs with the friction method. You want the electrons to build up and stay put…not to flow off the surface.
BEING EC’STATIC’ 2
• If the leaves in an electroscope are repelling each other state what you know about the charge of each leaf.
• Would you be able to state the sign of their charge? (positive or negative)
BEING EC’STATIC’ 2
• They have same charge, but you can’t tell if that charge is either positive or negative
BEING EC’STATIC’3
It is believed negative charge builds up in the base of a cloud and that leads to the ground having a positive charge.What method of charging is causing the ground to have this charge?How does itcreate the positivecharge?
BEING EC’STATIC’ 3
• Induction….the electric field of the cloud pushes electrons on the ground away; thereby inducing a positive charge on the ground
BEING EC’STATIC’ 4
• If electrons transfer from a charged object to a neutral one, the process of charging called ____________ has occurred and the act of the electrons making that jump is known as electric___________.
BEING EC’STATIC’ 4
• Conduction, discharge
Staying Current 1
• Pick the items that create voltage: a light bulba batterya wirea photocellan electric motora switch
Staying Current 1
a light bulba batterya wirea photocellan electric motora switch
Staying Current 2
The term “potential difference” refers to the circuit’s _______________
Staying Current 2
• voltage
Staying Current 3
Measuring the rate of the electricity’s ability to do work is when you measure ____________ and the units are ________________
Whereas, electrical energy is measured in ___________
Staying Current 3
• Power, watts, joules (or kilowatt-hours)
Staying Current 4
• A 9 volt battery is connected to an open circuit that has a total resistance of 8 ohms. How much current is flowing in it? (give answer in proper units of measure)
Staying Current 4
• Zero amps. (open circuit!)
Circuit Training 1
Which circuit would have higherresistance? Why?
Circuit Training 1
• The series circuit on the left has higher resistance. Parallel circuits have more branches which allows electrons to flow freer in more “lanes”; yielding lower resistance
Circuit Training 2
• Placing a switch between points 3 and 4 in the circuit will cause what to occur when the switch is opened?
• (R1, R2, R3 are light Bulbs)• R2D2 is a droid
Circuit Training 2
• The “R3” to turn off.
Circuit Training 3
1) Will this bulb light?2) Is this a regular circuit
or a short circuit?
Circuit Training 3
• 1) no• 2) it’s a short circuit
Circuit Training 4
• List the four properties of the circuit parts that affect resistance in a circuit
Circuit Training 4
• Thickness of parts, length of circuit, temperature of parts, materials used in circuit
By the Numbers 1
• If a circuit has 20 ohms of resistance and is running with 20 amps of current, what is the voltage?
By the Numbers 1
• V= IR• V= 20 amps * 20 ohms= 400 volts
By the Numbers 2
• If the circuit of an appliance is closed for 60 seconds and is using 600 J of energy, what power is used by the appliance?
By the Numbers 2
• E= PT• So E/T=P
600 J/ 60 s= 10 Watts
By the Numbers 3
• A circuit has 10 Ω resistance under normal conditions.
• A short circuit occurs and the circuit’s current jumps to 10 amps. It was at 1 amp before the short circuit.
• It’s voltage is set at 10 V.• What is the resistance of the short circuit?
By the Numbers 3
• R=V/I
• 10 V/ 10A= 1 Ω
By the Numbers 4Calculate the current of this circuit
By the Numbers 4
• Total resistance = 18 ohms• Voltage= 9 V• V/R= I• So, answer is 9 V/ 18 ohms= .5A
