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ELECTRICITY Chapter 7

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Page 1: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

ELECTRICITYChapter 7

Page 2: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Positive and Negative Charges

Protons = positive charge Electrons = negative charge

Most atoms have the same number of protons and electrons and thus will have no net charge. Atoms become charged when they gain or

lose electrons.

Page 3: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Static Electricity

The accumulation of excess electric charges on an object

Page 4: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Electricity obeys rules???

Law of conservation of charges - Charges can be transferred from object to object, but cannot be created or destroyed.

Opposite charges attract, like charges repel.

electrons move easier through conductors ex. metals

Electrons do not move easy through insulators ex. plastic, wood, rubber, and glass

Page 5: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Transferring Electric Charge

Charging by contact process of transferring charge by touching or

rubbing Ex. Static electricity from rubbing your feet on

carpet Charge by induction

the rearrangement of electrons on a neutral object caused by a nearby charged object Ex. a negatively charged balloon near your

sleeve causes an area of your sleeve to become positively charged

Page 6: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Transferring Electric Charge

Static discharge A transfer of charge through the air b/w two

objects because of a buildup of static electricity

Ex. Lightning

Page 7: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Read Page 197 Write and Answer the following questions

1. When the warm humid air rises to meet the cold air, what causes the air masses to churn together?

2. What electric property causes the negative charges in the cloud to be attracted to the positive charges in the ground?

3. Why does the ground below a cloud have a concentration of positive charges?

Page 8: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

ELECTRIC CURRENTChapter 7 Sec 2

Page 9: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Electric current

The flow of charges through a conductor (like a wire) is called electric current. Usually the flow of electrons Measured in Amperes (A) Flow from high to low voltage.

A voltage difference is the push that causes charges to move.

Voltage difference is measured in volts (V).

Page 10: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Circuit

For charges to flow, the wire or conductor must always be connected in a closed path called a circuit.

Page 11: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Sources of Electricity

Dry Cell Battery

Wet Cell Battery

Wall Socket

Page 12: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Sources of Electricity

Dry cell battery - produces voltage difference b/w its zinc container and its carbon suspension rod, causing current to flow b/w them

Wet cell battery – contains two connected plates made of different metals in a conducting solution.

Wall sockets – have a voltage difference across the two holes of an electrical outlet, and a generator at a power plant provides this voltage difference

Page 13: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Resistance

The tendency for a material to oppose the flow of electrons, changing electrical energy into thermal energy and light. All materials have some electrical resistance.

Measured in ohms (Ω) Making wires thinner, longer, or hotter

increases the resistance.

Page 14: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Ohms Law

current (in amperes) = voltage difference (in volts)

resistance (in ohms)

I = V/R

Page 15: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no
Page 16: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Ohms Law

Example Problem #1: What is the current in a 30V circuit if the resistance is 6Ω?

current (in amperes) = voltage difference (in volts)

resistance (in ohms)I = ?V = 30VR = 6Ω

Page 17: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Ohms Law

Example Problem #2: An Ipod uses a standard 3.7 V battery. How much resistance is in the circuit if it uses a current of 0.025 A?

current (in amperes) = voltage difference (in volts) resistance (in ohms)

I = V/R

Page 18: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

ELECTRICAL CIRCUITS

Chapter 7 Section 3

Page 19: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Series Circuit

Series circuit - The current only has one loop to flow through Parts of the circuit

are wired one after another, so the amount of current is the same through every part

Ex. String of holiday lights

Page 20: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Parallel Circuit

Parallel circuit – contains two or more branches for current to move through Parts can be

turned off without affecting the entire circuit

Ex. the electrical system in a house

Page 21: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Household Circuits

Parallel circuits connected in a logical network.

Electric energy enters your home at the circuit breaker or fuse box and branches out to wall sockets, lights, and major appliances

Guards against overheating Electric fuse Circuit breaker

Page 22: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Electrical Energy

Electrical energy is easily converted to thermal, radiant or mechanical energy. Electrical power – the rate at which electrical

energy is converted to another form of energy Electrical power is expressed in watts (W). Power = current X voltage difference P(watts) = I (amperes) X V (volts)

Page 23: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Example Problem

Your microwave runs at a current of 10 amps. A standard plug in your house has a voltage difference of 120 volts. How much electrical power does it take to run this appliance?

P = I x V

Page 24: Chapter 7. Protons = positive charge Electrons = negative charge Most atoms have the same number of protons and electrons and thus will have no

Example problem 2

If it takes 1750 watts of power to run my hairdryer, and we know that it is plugged up to 120 volt outlet what must be the current?

P = I x V


Protons, Electrons, and Neutrons Charges: Electrons - Negatively charged Protons - Positively charged Neutrons – Neutral (no charge)

Electricity. Electric Charge Rules: –More protons than electrons: + charge –More electrons than protons: - charge –Like charges repel; opposite charges

ATOMS & THE PERIODIC TABLE. Subatomic Particles Protons and electrons are the only particles that have a charge. Protons and neutrons have essentially

Basic Chemistry and Organic Compounds. Atoms : smallest unit of matter Protons: + charge, in nucleus Neutrons: 0 charge, in nucleus Electrons: - charge,

Electricity and Magnetism Protons have a ________ charge Electrons have a ________ charge Most atoms are neutral because_____ To become charge and atom

Electricity: Section 1 Electric Charge A. Protons have positive electric charge; electrons have negative electric charge. 1. In most atoms, the charges

By: Aimee Chavez. Protons: positive + charge, found in nucleus, Protons: Electrons: negative - charge, found outside nucleus Electrons: Neutrons:

What Gives an Electric Charge? An imbalance of protons and electrons. An imbalance of protons and electrons. Neutral objects have equal numbers of electrons

Biochemistry The Atom Smallest unit of an ____________ Three particles –Protons (___ charge) –Neutrons (__ charge) –Electrons (__ charge) _________

Chapter 7 Electricity. What is Charge? Protons have a (+) charge Electrons have a (-) charge Charge (q) is measured in Coulombs The elementary charge

CHEMISTRY Basic Chemistry. BASIC TERMS ATOM Smallest particle of a chemical element. –Consists of 3 parts. Protons = (+) charge Electrons = (-) charge

__________. Charge and Force All matter is made of atoms that contain ______________________, and protons Recall that protons and electrons in atoms have

Electric Charge. Atoms Small particles of matter Composed of 3 smaller particles: Protons = positive (+) charge Electrons = negative (-) charge Neutrons

Chemistry of Anatomy and Physiology. Atoms Smallest unit of an element Subatomic particles Protons: (+) charge Neutrons: neutral Electrons: (-) charge

Electricity - Edl · Web viewElectricity 7-1 Atoms contain particles called protons, neutrons, and electrons. Protons and electrons have electric charge, and neutrons have

Composition of Matter Atom= building block of an element Smallest part of matter Protons= + charge Neutrons= 0 charge Electrons= -1 charge

Electrons & Protons

Protons, Neutrons, Electrons

Electric Charge Electrically neutral – most objects have equal amounts of protons & electrons & therefore no net charge An intrinsic characteristic of

Electric Charges Types and Sources of Electric Charge Two kinds of electric charge – positive negative electrons protons

404094-EBimages.carsondellosa.com/media/cd/pdfs/Activities/...The ( protons / electrons / neutrons ) have no charge. 6. In most atoms, the number of protons and electrons are ( equal

Nuclear chemistry. Subatomic Particles Protons- plus charge In the nucleus Neutrons- neutral Electrons - negative charge Outside the nucleus

EHS RADIATION SAFETY TRAININGelectrons.The number of electrons and protons are equal. • Protons have a positive charge. Neutrons have ... Coulombs/kg. It is the amount of charge

Electric Charge and Static Electricity Notes. Electric Charge Electric charge is a property of protons and electrons. Protons have a positive charge

Electric Charge and Electric Force. What is an Electric Charge? Protons have positive (+) electric charge Electrons have negative (-) electric charge

ELECTRICITY. Electric Charge Protons and electrons both have the property of charge. Recall that protons are positive and electrons are negative

Protons = _________Charge Electrons = _________ Charge Neutrons =__________ Charge When Protons = Electrons are said to be ELECTRICALLY NEUTRAL

Atoms contain particles called protons, neutrons, and electrons. Protons and electrons have electric charge, and neutrons have no electric charge. Positive

Electricity. Charges Atoms contain particles called protons, neutrons, and electrons. Protons (+) Electrons (-) Neutrons (0)

Electric Charges. Alittlechemistry All matter Atoms are is made up of atoms made of protons, neutrons, and electrons Protons: (+) Neutrons ( no charge

Electricity is related to charges, and both electrons (-) and protons (+) carry a charge. Electricity is related to charges, and both electrons (-) and

Chapter Seven Atomic Structure neutrons atoms protons ( positive charge ) electrons ( negative charge )

Describe the mass, charge, and location of protons, neutrons, and electrons in atoms. S-105

Subatomic Particles Electrons, Protons and Neutrons and Their Electrical Charge

STATIC ELECTRICITY Electric charge 12 p+ Atoms are neutral Same # of protons as electrons