3/11/2015• My Questions and My Questions and

then your Questions then your Questions on the subjecton the subject

• Breaking electricity Breaking electricity in twoin two

• ElectrostaticsElectrostatics

3/12/2015

• Electricity question

• Electrostatics

• Voltage

• Leyden Jars

• Static Electricity Lab

My Questions:• What is electricity?What is electricity?

• What is static electricity?What is static electricity?

• How does a battery work?How does a battery work?

• What is one question you have What is one question you have always wondered about electricity always wondered about electricity or what you think is electricity? or what you think is electricity?

Your Question:

Thought Provoking Question about Electricity!

What causes electrical shock, current or voltage?

History of Electricity Part 1

600 BC

Thales of Miletus

Attractive properties of Amber

Thales of Miletus, a Greek philosopher, is believed to be the first person to have observed the attractive properties of amber. (His teachings were passed down orally until Aristotle wrote them down.) He observed that when rubbed, amber could pick up light objects.

Electrostatics is the study of electric charges at rest. It refers to the field of science called static electricity. It includes the topics of charge, voltage and electric forces. Sparks, lightning and “static cling” are examples.

Gilbert called these substances “electrics”. Eventually it was shown that every body acquires the ability to attract small bits of matter after it has been rubbed by another body. Bodies showing this attracting property are said to have an “electric charge” or to be electrified.

3/17/2015•Electrostatics

•Electric Charge

•How charge is created

Electric ChargePositive charge comes from having more protons than electrons and negative charge comes from having more electrons than protons. The most important concept, electrically, is that they have a property called "charge" which is the same size, but opposite in polarity for the proton and electron. The proton has 1836 times the mass of the electron, but exactly the same size charge, only positive rather than negative.

+

-

History of Electricity Part 8

AD 1791

Luigi Galvani

Theory of Animal Electricity

Luigi Galvani was dissecting a frog in his laboratory on a table near an electric machine generating sparks. He noticed that the frog leg jumped when a metal scalpel touched a nerve.

Electric ChargeThe phenomena of two objects sticking together can be explained by the notion that objects when rubbed can gain a net electric charge. There are two types of charge, labeled positive ( + ) and negative ( - ), with the following basic property:

•Like charges of the same sign repel each other.

•Unlike charges of the opposite sign attract each other.

•Charge is never created nor destroyed - it is conserved.

•Charge always comes in an integral multiple of a basic unit - it is quantized.

3/18/2015• Wave Review

• Finishing the toy car

• Electrostatics

• Voltage

• Static Electricity Lab

Electrically charged objects are usually formed when neutral objects lose or gain “charge” (electrons).

Excess of “electrons” s

Deficiency of “electrons”

Static Electricity

The Science of Static Electricity

Static electricity is produced when one object takes negative charges from another object. For example, amber becomes negatively charged when rubbed with wool, because amber attracts negative charges (electrons) and will take them from wool. As a result, the amber becomes "negatively charged," and the wool, due to its loss of negative charges, becomes "positively charged".

Triboelectric Series

Rabbit fur

Glass

Human hair

Nylon

Wool

Silk

Paper

Cotton

hard rubber

polyester

Styrofoam

Saran Wrap

Scotch Tape

PVC

Silicon

Teflon

Mor

e po

siti

ve

More negative

If objects are rubbed together, “charge” may be transferred between them.

Static Electricity

Oppositely charged objects are attracted by an electric force.

Same charged objects are repelled by an electric force.

Weird: a pickle, a fan and a hot dog. What to

do when you are hungry and afraid of

the dark.

It’s ALIVE!!!It’s ALIVE!!!

Thought Provoking Question about Electricity!

Why is it we Why is it we only see the only see the Aurora Borealis Aurora Borealis at higher at higher latitudes?latitudes?Could we have and aurora without the sun?

4/14/2014• Wave Test

• BLOOD MOON

• Electrostatics

• Voltage

• Static Electricity Lab

4/28/2014

• Electricity question

• Electrostatics

• Voltage

• Leyden Jars

• Static Electricity Lab

Explanations?Based on the what you saw, what are the

individual components of the demonstration?

Triboelectric Rule

A charged object will attract a neutral object by inducing a charge.

3/25/2015

• Turn in Lab

• Electrostatics–Coulomb’s Law

–The electric field

If a system consists only of neutral objects, it has a total net charge of zero. If electrons are transferred within the system and one object gains electrons and another loses electrons, the system has a whole is still neutral.

The statement that in a closed, isolated system, the total charge of the system remains constant is known as the law of conservation of charge.

q1 q2r

Fe = kq1q2

r2=

•There must be a net charge for a field to exist.•Field lines are smooth curves or straight lines.•The larger the charges, the more field lines.

Field strength depends on charge strength.•Field lines go from positive to negative.

3/25/2015• Check your grades onlineCheck your grades online• Electric FieldElectric Field• Graphing the electric fieldGraphing the electric field

Candle flame, Coulomb force

Electric Field Creation

Electric Field Destruction

Electric Field Repulsion/Attraction

d+q +q

3/26/15• Glowing

Stuff in a field?

• Mapping the electric field using voltage

•Check wikipedia•Hyperphysics•Eskimo.com•Physics textbook

Lab

on

Ele

ctri

c fi

eld

3/31/20153/31/2015• Lab Due Thursday

• What happens when electric charges start to move?

• Cool Stuff

4/1/20154/1/2015• Lab Due Thursday

• What happens when electric charges start to move?

VOLTAGE: is an electric potential difference between two points on a conducting wire. Voltage is measured in volts. Voltage comes from various sources. Two examples of these sources are batteries and electrical outlets.

Potential Difference

CURRENT: is measured in amps. Current is charged particles which flow from the voltage source through conductive material to a ground.

not the band

What is the difference between alternating and direct current?

Which do you use to power appliances at home?

Direct Current (DC) is produced by batteries, fuel cells and solar cells.Current always flows in the same direction. Negative terminal to positive terminal.

Name given to the electrical current coming from the power plant to your home.

The direction of the current reverses, or alternates, 60 times per second (in US) or 50

times per second (in Europe).Wall socket in US will give you 120 V and 60

Hz AC power.

4/2/20154/2/2015• Lab Due today

• What happens when electric charges start to move?

• Current electricity

The Problem with The Problem with TopsyTopsyHave a little more history with your physics.

4/13/2015

• Electric Potential

• Voltage

• Equipotential Surfaces

• Capacitors

• Current Electricity Intro

Can’t change the voltage

In order to travel long distances you need to have very thick wires and very high voltages.

The cycling the current allows you to change voltage easily.

You can send current over large distances with small wires.

The SI unit of electric current, I, is the ampere, A. It is a fundamental unit. The coulomb, C, the unit of charge is a derived unit defined to be the amount of charge that passes a point when a current of one ampere flows for one second.

An ammeter is a device used to measure current.

Electric current, I, is the rate at which current passes a cross section:

is the opposition that a material body offers to the passage of an electric current. Resistance is measured in ohms. Examples of items with resistance are light bulbs, hair dryers, toasters.

Electric current is the rate of charge flow past a given point in an electric circuit, measured in coulombs/second which is named amperes. In most DC electric circuits, it can be assumed that the resistance to current flow is a constant so that the current in the circuit is related to voltage and resistance by Ohm’s Law.

RESISTANCE: is the opposition that a material body offers to the passage of an electric current. Resistance is measured in ohms. Examples of items with resistance are light bulbs, hair dryers, toasters.

The simplest electric circuit consists of a source of electrical energy, a battery, connecting wires, and a circuit element such as a lamp or a resistor that converts electrical energy to light or heat.

+

4/14/154/14/15• Ohms Law LabOhms Law Lab

• The “Electric Man”The “Electric Man”

• Circuit LabCircuit Lab

Electric current is the rate of charge flow past a given point in an electric circuit, measured in coulombs/second which is named amperes. In most DC electric circuits, it can be assumed that the resistance to current flow is a constant so that the current in the circuit is related to voltage and resistance by Ohm’s Law.

It is worth noting that current flows through a resistor and voltage is always across a resistor.

Voltage never flows through anything and current is never across anything.

4/16/2015

• Series and Parallel Series and Parallel Circuits Circuits

•One path for current to flow through.

•A Single break anywhere along the path and current will stop.

•In parallel circuits more than one path for current to flow is provided.

•If a break occurs along the line in one spot, current to the other places will still flow.

4/21/2015

• Series and Parallel Series and Parallel Circuits Circuits

VT = V1 + V2 +V3

IT = I1 = I2 = I3

RT = R1 + R2 +R3

Req = R1 + R2 + R3

Req = 12

4/22/2015• Series and Parallel CircuitsSeries and Parallel Circuits

• Magnetism Magnetism

• Electromagnetic Induction Electromagnetic Induction

Series Circuit

• All bulbs are dependant upon each other

• If one bulb goes out all the rest go out.

• Bulbs in series divide up the energy and therefore appear dimmer as more bulbs are added.

+

-

1

2

3

Parallel Circuit

• All bulbs are independent from the rest.

• If one bulb goes out all the rest stay lit.

• Bulbs in parallel each get full energy and therefore brightness does not change as more bulbs are added.

-

+

1 2

All matter is composed of atoms, and atoms are composed of protons and neutrons located in the atom's nucleus and electrons that are in constant motion around the nucleus. Electrons carry a negative electrical charge and produce a magnetic field as they move through space. A magnetic field is produced whenever an electrical charge is in motion.

Magnetism is the force of attraction or repulsion between magnetic poles. Magnetic poles are the opposite ends of a magnet where the magnetic force is the strongest. Magnetic force is produced by the motion of charges relative to each other.

Magnetic field is the region where the magnetic force exists around a magnetic or any moving charged object. It exerts a force on any other moving charge.

What rule applies to magnets as well as electric charges?

Where are magnetic fields strongest?

AT THE POLES!NOTEBOOK!

Can you figure out the polarity of magnets B and C?

Andrew Crosby likes wearing hats.

Draw this in your notebook….

Electromagnetic Induction (EMI)

• EMI was the discovery that moving a coil of wire past a magnetic field creates an electric current and an electric current through a coil of wire creates a magnetic field!

=Current!NOTEBOOK!

How to make an electromagnet stronger…

• Increase number of coils

• Increase the voltage

• Use iron based cores

NOTEBOOK!

Current Through a Coil Makes a BIG Magnet!

What is a Rail Gun?

VT= V1=V2=V3 48 V48 V

24 A

12 A

8 A

IT= I1+ I2+ I3

Req = VT / IT

Req = 1.1