Transcript POWERPOINT JEOPARDY

Static
Electricity
Circuits
Circuits
Part Deux
Safety
In the
House
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Question 1 - 10
• What is electricity
Answer 1 – 10
• Electricity is the set of physical phenomena
associated with the presence and flow of
electric charge.
Question 1 - 20
• If you rub plastic and fur together what will
happen, with respect to charge, to each of
those substances?
Answer 1 – 20
• Fur will loose electrons and become positively
charged and plastic will gain electrons and
become negatively charged.
Question 1 - 30
• What is conductivity and how does an
insulator differ from a conductor?
– Be sure to include an example of the conductor
and the insulator.
Answer 1 – 30
• Conductivity – ability of materials to allow
electrons to move freely in them
– Insulator – solid, liquid or gas resisting flow of
electrons
– Conductor – solid, liquid or gas allowing flow of
electrons
Question 1 - 40
• If you were to bring a negatively charged
balloon close to a wall. Explain, using two
laws, what will happen to the charges in the
wall.
Answer 1 – 40
• Negative will move inward, positive will
remain to hold balloon
• Law of Attraction and Repulsion
– Opposites attract
– Like charges repel
Question 1 - 50
• What is an electroscope and how does it
demonstrate induction?
Answer 1 – 50
• Electroscope – detects static charge
• Induction
– movement of electrons within a substance caused
by a nearby charged object, without direct contact
between the substance and the object.
Question 2 - 10
• Draw and name three symbols from a
schematic circuit diagram.
Answer 2 – 10
Question 2 - 20
• What is an electrochemical cell?
– How does an electrolyte differ from an electrode
in an electrochemical cell?
Answer 2 – 20
• A battery is a combination of electrochemical
cells
– Electrochemical cells are packages of chemicals that
convert chemical energy into electrical energy
– Electrolyte – liquid or paste that conducts electricity
because it contains chemicals that form ions.
– Electrodes – metal strips that react with the
electrolyte
– Chemical reaction allows electrons to collect on one
of the electrodes making it negatively charged.
Question 2 - 30
• Draw a schematic diagram for a circuit with a
9V battery, two equal resistors, a switch an
ammeter and a voltmeter measuring current
across one of the resistors indicating what the
voltage would be.
Answer 2 – 30
• Diagram
Question 2 - 40
• How does a wet cell differ from a dry cell? Be
sure to include examples.
Answer 2 – 40
• Dry cell – uses a paste electrolyte
• Wet cell – uses a liquid electrolyte
Question 2 - 50
• Please define current, voltage and resistance.
Answer 2 – 50
• The difference in electrical potential energy between
two points in a circuit is called the potential difference
• Electric Current is a measure of the amount of electric
charge that passes a point in an electric circuit each
second.
• Degree to which a substance opposes flow of electric
current through it.
– This resistance slows down the flow of electrons and therefore
it slows down the current and converts electrical energy into
other forms of energy
Question 3 - 10
• How does a series circuit differ from a parallel
circuit?
Answer 3 – 10
• Parallel - Components are arranged so that
electrons can flow along more than one path
– A break does not affect all loads
• Components are arranged one after another
in series
– One light goes out, they all go out
– Add more resistance and you decrease the current
Question 3 - 20
• Draw a parallel circuit with a 9V battery, three
resistors each with its own switch, an
ammeter measuring current out of the second
resistor and a voltmeter measuring the
voltage across the third resistor.
Answer 3 – 20
• Drawing
Question 3 - 30
• What is Ohm’s Law
Answer 3 – 30
• As long as temperature stays the same, V=IR
Question 3 - 40
• A current of 2.3 A flows through a 50 ohm
resistor that is connect to a battery. What is
the voltage of the battery?
Answer 3 – 40
• 115 V
Question 3 - 50
• A current of 675 mA runs through a resistor
that is connected to a 120 V power supply.
What is the resistance of the bulb?
Answer 3 – 50
• 177.78 ohms
Question 4 - 10
• What is a short circuit?
Answer 4 – 10
• Accidental low resistance connection between
two points in a circuit, causing excess current
flow.
• Electrical devices will not work and will be
dangerous – heat or fire.
Question 4 - 20
• Compare and contrast fuses and circuit
breakers.
Answer 4 – 20
• Fuse = safety device in an electrical circuit that
has a low melting point, compared to wires.
• Circuit breaker = does the same thing but
instead of melting, the wire heats up and
bends which triggers a spring mechanism to
turn off the electricity
Question 4 - 30
• Identify two electrical safety devices involved
with plugging in an appliance.
– Think plug and appliance
– Explain how they work.
Answer 4 – 30
Question 4 - 40
• Why must you avoid frayed electrical cords.
Answer 4 – 40
• Electric Shock…short circuit.
Question 4 - 50
• You want to find the value of an unknown
resistor however you have access to a
multimeter.
• How could you figure it out?
Answer 4 – 50
• R = V/I
• Use the ohmmeter function
Question 5 - 10
• What does time of use (TOU) electricity billing
mean?
Answer 5 – 10
• Smart meters send usage of electricity on a house by
house basis to the electric company so that the
house gets charged the right amount
Question 5 - 20
• If a kettle uses 1.5 kW per hour and you have
it on for 15 minutes every day, how much
does your energy cost per year.
– Assume energy costs you $0.105/hour.
Answer 5 – 20
• $14.37
Question 5 - 30
• What is the percent efficiency of a bulb that
has 1000 joules of energy going in but only
600 joules of energy coming out?
Answer 5 – 30
• 600/1000 x 100 = 60% efficient
Question 5 - 40
• How does Energuide differ from Enerstar?
Answer 5 – 40
• Energuide – average energy use in a month or
year for an appliance compared to other
similar appliances.
• Energy Star – means the appliance is one of
the most efficient appliances in its class.
Question 5 - 50
• What are 5 things you can do at home to
reduce energy consumption, or at least reduce
the cost of your energy bill.
Answer 5 – 50
• OPEN