Aim: What is electric charge? (Monday)Do Now: What are 2 types of electric charge?Homework: Read pgs 392 – 394 &

Study for Quiz1. What is matter?

2. What is all matter made from?

• Anything that has mass & volume

Examples:

Solids, Liquids, Gases

• Atoms

3. What are the building blocks of an atom?

1. Protons,

2. Neutrons &

3. Electrons

4. Where are these subatomic particles located in the atom?

1. In the Nucleus (center of atom)

Protons & Neutrons

2. Electrons move around the nucleus in energy levels

(also called shells or orbits)

5. What is the electrical charge on the subatomic particles?

1. Protons = Positive charge or (+)

2. Electrons = Negative charge or (-)

3. Neutrons = Neutral or No Charge

The Structure of an Atom

6. What makes atoms electrically neutral?

(no charge)

# of protons

=

# of electrons

Example:

Hydrogen has

1 protons &

1 electrons

Therefore: + 1

-1

0

7. How would an atom gain a negative charge?

(-)

8. How would an atom gain a positive charge?

(+)

It must gain one or more electrons

It must lose one or more electrons

Hydrogen

Normally Neutral

Gains an Electron = Neg. Charge

Loses an Electron = Pos. Charge

+1

-1

+1

-2

+1

0

0 -1 +1

What part of the atom is gained or lost?

• ONLY the Electrons

• Never Protons

9. What is the Law of Electric Charge?

1. A force of attraction exists between oppositely charged particles(+) & (-)

2. Like charges repel each other(+) & (+) or (-) & (-)

Law of Charges

Quiz (The Atom)

1. What type of charge do electrons have?

2. What would make an atom electrically neutral?

3. Anything that has mass & volume is known as _____________.

4. The nucleus of an atom contains both ____________ & ___________.

5. What type of charge do neutrons have?

Quiz (The Atom)

6. Do oppositely charged particles attract or repel each other?

7. Protons have a _________ charge.

8. How does an atom gain a negative charge?

9. What part of the atom is gained or lost?

10. How would an atom gain a positive charge?

Aim: How can objects become charged? (Tuesday) (3 Methods)

Do Now: Prepare for Quiz.Homework: Read pgs 395 – 399 &

Study for Quiz1. How does a

neutral object acquire an electric charge?

2. What are 3 ways to charge an object?

• Electrons are either gained or removed

1. Friction,

2. Conduction &

3. Induction

3. What is friction?

4. What can cause friction?

5. How can this create a charge?

• The force that opposes motion

• Rubbing 2 objects together

• Electrons are removed from one object & gained by the other object

6. What happens to a balloon when you rub it against a cloth?

a) The balloon gains electrons

(negative charge)

b) The cloth loses electrons

(positive charge)

7. What causes the balloon to stick to the wall?

1. The electrons in the wall are repelled by the negative charges on the balloon

2. The positive charges in the wall are attracted to the balloon

Balloon & Cloth

8. How is an object charged by conduction?

9. What materials allow electrons to flow freely?

a) Through direct contact

b) Electrons can flow through one object to another

ConductorsExample - • Metals such as: Silver, Copper,

Aluminum &• The Earth

10.What materials do not allow electrons to flow freely?

Note: Good conductors & insulators of ELECTRICITY

Insulators

Example –

rubber, glass, wood, plastic, air

Good conductors & insulators of HEAT

11. How is an object charged by induction?

a) Rearrangement of electric charges

b) No Contact is necessary

Example:

The negatively charged rubber rod causes the meter stick to move without touching it

12. How is induction different from conduction?

a) Conduction involves Direct Contact

b) Induction – No direct contact

Quiz (Charging)

1. What materials do not allow electrons to flow freely (conductors or insulators)?The next 3 answers pick: friction, conduction, or

induction

2. What method of charging occurs through direct contact?

3. What type of charging occurs when the charges on a neutral object are rearranged (redistributed)?

4. What is the force that opposes motion?

Quiz (Charging)

5. Good conductors & insulators of electricity are also good conductors & insulators of __________.

6. What caused the rubber rod to become negatively charged?

7. How can an object become charged without direct contact?(friction, conduction, induction)

8. What is an example of a good conductor?

Quiz (Charging)

9. What happened to the balloon when we rubbed it against the rabbit’s fur?

10.What happened to the rabbit’s fur?

Bonus: What happened to the number of protons on the balloon & rabbit’s fur?

Aim: What is lightning?Do Now: Prepare for Quiz.Homework: Study for Quiz (Wednesday)1. What

type of charge is shown in the pictures?

2. What causes lightning?

1. Static Electricity

&

2. Electric Discharge

3. What is static electricity?

a) The buildup of electric charges on an object without further movement

b) This is caused by friction

4. What is electric discharge?

a) The loss of static electricity as electrons move off an object

b) As electrons move through the air:

• noise may be heard • a spark of light can

be seen• you may feel a shock

1. What causes the clouds to be charged?2. What causes the ground to be positively charged?

5. What can be used to protect a building?

a) A lightning rod

b) Made from:

Metal

c) Positioned:

Higher than the building

6. What instrument can be used to detect an electric charge?

An electroscope

7. How does an electroscope work?

a) Normally, the metal leaves hang freely

b) If a negatively charged rod touches the metal ball on top, electrons move down both leaves

c) Like charges repel each other, & the leaves spread out

8. What happens if a positively charged glass rod touches the metal ball on the electroscope?

a) Electrons from the electroscope are attracted to the rod & flow up into the rod

b) Both leaves become positively charged

c) They repel & spread out

Quiz (Static Electricity)1. The loss of static electricity is known as

_____________.

2. An instrument used to detect electric charge is known as ____________.

3. The build-up of electric charge without further movement is known as _________.

4. What types of materials are lightning rods made from?

5. Static electricity is caused by __________.

Aim: How is the flow of electricity created?Do Now: Prepare for Quiz.Homework: Read pgs 400 – 404 &

Study for Quiz (Thursday)

1. What is the flow of electricity called?

a) Electric Current

b) Or the amount of charge that passes a given point per unit time

Recall Questions

• What are 2 types of charges?

• What materials allow electrons to flow freely?

• What materials hold on tightly to their electrons?

• Positive & Negative

• Conductors

Examples?

• Insulators

Examples?

2. What symbol represents “current”?

3. What units are used to measure current?

Capital letter:

I

The ampere or

amp

= the amt. of current that flows past a point per sec.

4. Within the wire, what opposes the flow of electric charge (current)?

(This is like you walking down the hallway!)

a) Resistance, or

R

b) Resistance depends upon:

The material of the wire

The thickness & length of the wire

Temperature

• As the thickness of a wire increases, the resistance will ___________.

• As the length of a wire increases, the resistance will _____________.

• As resistance increases, current ______.

• If it is difficult for electric charge to flow through a material, resistance _________.

• What happens to resistance at very low temperatures?

decrease

increase

decreases

is higher

decrease

5. What is the unit for resistance?

6. How is resistance necessary in a light bulb?

the ohm or (Ω)

The metal filament in the center offers enough resistance to the electric current flowing through it causing

LIGHT & HEAT to be given off

7. What causes an electric charge to move?

a) WORKRemember: Work =

Force X Distance

b) The amount of work required to move a charge between 2 points is the:

Electric Potential Difference

8. What is the unit of potential difference?

9. What are some examples of voltage?

a) The volt (V)

b) The term Voltage is often used for potential difference

1. Batteries

2. Electric generators

3. Thermocouples

4. Photo cells

Batteries containing Electrochemical Cells

A Thermocouple produces electrical energy from heat energy

(temperature differences)

Aim: 1. How are current, resistance, (Friday) voltage related to each other?

2. What is the difference between direct current & alternating current?Homework: Study all notes from this week for

Monday’s Quiz.

1. What is Ohm’s Law?

(What is an ohm?)

This states:The current in a wire (I) is = to the voltage (V) divided by the resistance (R)

2. How can we use the magic triangle & Ohm’s Law?

1. I = V R

2. V = I R

3. R = V I

Recall:What are the units for each?

I

V

R

Problem:

A clothes iron is plugged into a 120 volt outlet & uses a current of 5 amps.

What is the resistance of the iron?

1. Formula:

R = V

I

2. Plug in numbers:

R = 120 V

5 amps

3. Calculate:

R = 24 Ω

Solve

3. What is the difference between direct current & alternating current?

1. Direct Current (DC):

electrons flow in the same way

ex. battery

2. Alternating Current (AC):

electrons move back & forth

The current in your house changes direction 120 times/sec!!!

Aim: What causes electricity to turn on & (Friday) off in your house?Do Now: What is the difference between direct & alternating current?

1. What is a circuit? A complete path through which electricity can flow

2. What are the 4 parts of a circuit?

1. Source of energy

(battery, outlet…)

2. A load, or resistance

(light bulb, machine, appliance…)

3. Wires

4. Switch

3. What is the purpose of a switch?

4. What is the problem with an open circuit?

It can open or close a circuit

• Electrons can’t travel through an open circuit

• When an electronic device is off, the circuit is open

Which picture shows an open circuit?

Electricity can only flow through a CLOSED circuit!!!

5. What are 2 types of circuits?

6. What is a series circuit?

Series Circuit&

Parallel Circuit

a) It has only one path for electrons to take

b) Disadvantage:if there is a break in any part, the entire circuit is open

***NO electricity can flow

7. What is a parallel circuit?

8. What happens if one light bulb burns out in a parallel circuit?

A circuit that provides several pathways for electrons to flow

The rest will stay lit because electrons can still move through the other branches

Which picture shows a parallel circuit?

9. What are some circuit safety devices?

a) Fuses

b) Circuit Breakers

• They protect against a circuit overload

(too much current flowing at once)

• by opening the circuit

10. How does the 3rd prong of a plug act as a safety device?

a) No electricity runs through it

b) It is connected directly to ground

c) Protects against accidental shock

Aim: What is magnetism?Do Now: Take out a piece of looseleaf

& Prepare for quiz.

1. The flow of electrons is known as_____________.

2. As the thickness of a wire increases, resistance ____________.

3. Give at least one example of a source of electrical potential difference.

4. Within a wire, what opposes the flow of electric current?

5. The units used for electric current are __________.

6. The units used for voltage are__________.

7. Electrons can’t travel through a(n) _______ circuit.

8. The type of circuit that has more than one pathway for electrons to travel is known as a _______circuit.

9. What would happen

to the other 2 light

bulbs in the picture

if the middle light

bulb didn’t work?

10. A clothes iron is plugged into a 120 volt outlet & uses a current of 10 amps.

What is the resistance of the iron?

Show the formula,

V calculation, answer & units

I R

Monday – December 17, 2007

Aim: What are properties of magnets?Do Now: Prepare for Quiz

Homework - Study for Quiz

Test on Electricity/Magnetism on Friday

Extra Help in Room 206 on Thursday

1. What is magnetism?

The force of attraction or repulsion of a magnetic material due to the arrangement of electrons in the atoms

Recall:• What is a force?• What are units of force?• How can you calculate

force?

What is happening in each picture?

2. On a magnet, where is the force noticed to be the strongest?

3. What is a magnetic field?

The ends a.k.a.

The North Pole & South Pole

The region around the magnet in which the magnetic force can act

The magnetic field lines go around the magnet in complete loops from the

North Pole to the

South Pole

4. What is the rule for magnetic poles?

• Like poles repel each other

• Unlike poles attract each other

5. Does the earth have a magnetic field?

• Yes! It has a North & South Pole.

• Believed to be related to the motion of the Earth’s outer core (made of iron & nickel)

• The Earth’s magnetic field has changed over time.

Tuesday – December 18, 2007

Aim: How can a magnet be made?Do Now: Prepare for Quiz

Homework - Study for Quiz

Test on Electricity/Magnetism on Friday

Operation Success this Wednesday at 3pm

1. The magnetic field lines go around the magnet in complete loops from the _________ Pole to the ________ Pole.

2. Like poles __________ each other.

3. The region around the magnet in which the magnetic force can act is called the __________ __________.

4. On a magnet, where is the force noticed to be the strongest?_______________

5. What is a force?_______________

Name_____________ Laws of Magnetism-Quiz

1. What types of materials can become magnetized?

2. What makes one material more magnetic than another?

Iron, Steel, Nickel, & Cobalt

a) When the electrons of the atoms all rotate in the same direction or

b) The magnetic domains all align

3. What are magnetic domains?

a) They are like minimagnets that make up the material

b) Unmagnetized materials have randomly arranged domains

c) Magnetized materials have most of the domains aligned

Which picture shows a magnetized object? Why?

4. How can a temporary magnet be made?

• Align the domains by:

1. Placing a strong permanent magnet by a magnetic material (soft iron)

2. Stroking a magnetic material with a permanent magnet In ONE Direction

5. How can a permanent magnet become unmagnetized?

• Make the domains random by:

1. Dropping or hitting it

2. Heat it

6. What is a permanent magnet made from?

• Materials that are difficult to magnetize, but tend to stay magnetized

• Many are called Alnico

• Made from a mixture of aluminum, nickel, cobalt, copper, & iron

Wednesday – December 19, 2007Aim: What is Electromagnetism?Do Now: Prepare for quiz

Homework - Study for Quiz

Test on Electricity/Magnetism on Friday

Operation Success this Wednesday at 3pm

Name_____________ Making a Magnet-Quiz

1. State one way a temporary magnet can be made._______________________________

2. Give one example of a material that can become magnetized.___________________

3. The mini-magnets that make up a magnet are know as magnetic _____________.

4. State one way a permanent magnet can become unmagnetized.________________________

5. Materials that have magnetic domains that are randomly arranged are ______________.

(magnetized/unmagnetized)

1. What is the relationship between an electric current & a magnetic field?

A current flowing through a wire gives rise to a magnetic field whose direction depends on the direction of the current

2. How do you make the magnetic field near a current carrying wire stronger?

 

1. Bend the wire into a series of coils to increase the number of turns. (Solenoid) 

2. Increase the current (flow of electrons)

3. Insert an iron core

3. What is an electromagnet?

a) A temporary magnet produced by an electric current.

b) Found in telephones, clocks, TV’s, car motors, doorbells

Why does this happen?

http://education.magnet.fsu.edu/curriculum/maglab_alpha/maglabalpha/html/movies/elect.mov

http://www.horsforth.leeds.sch.uk/subjects/physics/gcse/electromagnetism/images/g-phy-elmag-dia08.swf

4. Can electricity be made from magnetism?

Yes!!!• A changing (not

steady) magnetic field can create an electric current.

• This is an induced current or:

Electromagnetic Induction

How is electricity produced from magnetism?

How does a hand generator work?

Hand generator

Thursday – December 20, 2007Aim: Review: What do you know about

Electricity & Magnetism?Do Now: Prepare for quiz

Homework - Study for tomorrow’s Test on Electricity/Magnetism

Name_____________ Electromagnetism-Quiz

State 3 Ways an Electromagnet can become stronger1.2.3.4. What does this picture show?

5. A ____________ magnetic field can create an electric current.

What energy transformations are taking place here?

Fill in the “?”

The current in a simple circuit

• A simple electric circuit contains a source of voltage difference ,such as a battery ,a device ,such as light bulb that has resistance ,and conductors that connect the device to the battery terminals.

• In a series the current has only one loop to flow through. Series circuit are used in flash light and some holiday light circuit.

•A parallel circuit contain two or more branches for current to move though.