Physics II: Electricity & Magnetism Chapter 21 Sections 21-1 to 21-4 Chapter 21 Sections 21-1 to 21-4

Thursday (Day 2)

Journal Entry Thurs, Jan 22  What is the charge of a proton?  What is the charge of an electron?  What happens to a _______ charge when a _______ charge is around it?  positive; negative  positive; positive  negative; negative  negative; positive  Place your homework on my desk:  Student Information Sheet  “What do you know?” Packet (Part I) & Scantron Thurs, Jan 22  What is the charge of a proton?  What is the charge of an electron?  What happens to a _______ charge when a _______ charge is around it?  positive; negative  positive; positive  negative; negative  negative; positive  Place your homework on my desk:  Student Information Sheet  “What do you know?” Packet (Part I) & Scantron

Warm-Up Wed, Jan 21  Pick up the following handouts and find your seat:  “Foundational Mathematics’ Skills of Physics” Packet  Place your homework on my desk:  Not Applicable Wed, Jan 21  Pick up the following handouts and find your seat:  “Foundational Mathematics’ Skills of Physics” Packet  Place your homework on my desk:  Not Applicable

Essential Question(s)  WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?  HOW DO WE DESCRIBE THE NATURE OF ELECTROSTATICS AND APPLY IT TO VARIOUS SITUATIONS?  How do we describe and apply the concept of electric field?  How do we compare and contrast the basic properties of an insulator and a conductor?  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we describe and apply Coulomb ’ s Law and the Principle of Superposition?  WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?  HOW DO WE DESCRIBE THE NATURE OF ELECTROSTATICS AND APPLY IT TO VARIOUS SITUATIONS?  How do we describe and apply the concept of electric field?  How do we compare and contrast the basic properties of an insulator and a conductor?  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we describe and apply Coulomb ’ s Law and the Principle of Superposition?

Vocabulary  Static Electricity  Electric Charge  Positive / Negative  Attraction / Repulsion  Charging / Discharging  Friction  Induction  Conduction  Law of Conservation of Electric Charge  Static Electricity  Electric Charge  Positive / Negative  Attraction / Repulsion  Charging / Discharging  Friction  Induction  Conduction  Law of Conservation of Electric Charge  Non-polar Molecules  Polar Molecules  Ion  Ionic Compounds  Force  Test Charge  Electric Field  Field Lines  Electric Dipole  Dipole Moment  Non-polar Molecules  Polar Molecules  Ion  Ionic Compounds  Force  Test Charge  Electric Field  Field Lines  Electric Dipole  Dipole Moment

Foundational Mathematics Skills in Physics Timeline DayPg(s)DayPg(s)DayPg(s)DayPg(s) † WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?

Agenda  Introduction to Electrostatics  Pick up the following handouts:  “Foundational Mathematics’ Skills of Physics” Packet  “What do you know?” Packet (Part II)  Introduction to Electrostatics  Pick up the following handouts:  “Foundational Mathematics’ Skills of Physics” Packet  “What do you know?” Packet (Part II)

Chapters 21 & 22 Electric Charge and Electric Field; Gauss’s Law

Units of Chapter 21 Static Electricity; Electric Charge and Its Conservation Electric Charge in the Atom Insulators and Conductors Induced Charge; the Electroscope Coulomb’s Law Solving Problems Involving Coulomb’s Law and Vectors The Electric Field

Units of Chapter 21 & 22 Field Lines Electric Fields and Conductors Chaper 22 Electric Flux Gauss’s Law Electric Forces in Molecular Biology: DNA Structure and Replication

Section 21.1  How do we describe and apply the concept of electric field?  How do we describe the characteristics of a positive electric charge?  How do we describe the characteristics of a negative electric charge?  How do we describe the law of conservation of electric charge?  How do we describe and apply the concept of electric field?  How do we describe the characteristics of a positive electric charge?  How do we describe the characteristics of a negative electric charge?  How do we describe the law of conservation of electric charge?

21.1 Static Electricity; Electric Charge and Its Conservation Objects can be charged by rubbing

21.1 Static Electricity; Electric Charge and Its Conservation Charge comes in two types, positive and negative; like charges repel and opposite charges attract † Electricity comes from the Greek word elektron, which means “ amber ”

21.1 Static Electricity; Electric Charge and Its Conservation Electric charge is conserved – the arithmetic sum of the total charge cannot change in any interaction.

Section 21.2  How do we describe and apply the concept of electric field?  How do we describe electric charge in an atom?  How do we describe electric charge in a molecule (or formula unit)?  How do we describe and apply the concept of electric field?  How do we describe electric charge in an atom?  How do we describe electric charge in a molecule (or formula unit)?

21.2 Electric Charge in the Atom Atom: Nucleus (small, massive, positive charge) Electron cloud (large, very low density, negative charge)

Parts of the Atom  Location: Nucleus  Proton  Charge: 1.60 x Coulombs  Mass: x kg  Made of 2 up quarks and 1 down quark  Neutron  Charge: Neutral (0 Coulombs)  Mass: x kg  Made of 2 down quarks and 1 up quark  Location: Energy Levels in the Electron Cloud  Electrons  Charge: x Coulombs  Mass: 9.11 x kg  Location: Nucleus  Proton  Charge: 1.60 x Coulombs  Mass: x kg  Made of 2 up quarks and 1 down quark  Neutron  Charge: Neutral (0 Coulombs)  Mass: x kg  Made of 2 down quarks and 1 up quark  Location: Energy Levels in the Electron Cloud  Electrons  Charge: x Coulombs  Mass: 9.11 x kg

The Size of the Nucleus  Almost all of the mass of the atom is concentrated in its tiny nucleus.  Next Slide: the football field illustration.  Almost all of the mass of the atom is concentrated in its tiny nucleus.  Next Slide: the football field illustration.

If the nucleus were the size of a pinhead...

The Low Density of the Electron Cloud Model  The low density of the electron cloud is due to the fact that (1) the mass of one proton is equal to the mass of 1,836 electrons and (2) the electrons are arranged in the energy levels that are far from the nucleus.  The proton has 1,836 times more inertia than an electron and is therefore 1,836 times harder to move than an electron.  The low density of the electron cloud is due to the fact that (1) the mass of one proton is equal to the mass of 1,836 electrons and (2) the electrons are arranged in the energy levels that are far from the nucleus.  The proton has 1,836 times more inertia than an electron and is therefore 1,836 times harder to move than an electron.

INERTIA A Proton vs. an Electron  Recall Newton’s Second Law of Motion  Force = mass x acceleration  The proton has 1,836 times more mass (aka. Inertia) than an electron and is therefore 1,836 times harder to move than an electron.  Recall Newton’s Second Law of Motion  Force = mass x acceleration  The proton has 1,836 times more mass (aka. Inertia) than an electron and is therefore 1,836 times harder to move than an electron.

Electron Cloud Model  The probability of locating an electron 90% of the time is determined by utilizing the Schrödinger equation and statistics.

21.2 Electric Charge in the Atom Atom is electrically neutral. Rubbing charges objects by moving electrons from one to the other.

Chemical Bonding Atoms bond together to form electrically neutral substances. The type of chemical bond is determined by the electronegativity difference between the atoms involved.

Electronegativity Values: The Affinity for Electrons

Electronegativity Difference and Bond Type Electronegativity Difference Bond Type EN: Nonpolar Covalent Bond EN: Polar Covalent Bond EN: 1.66 and greater Ionic Bond

Nonpolar Covalent Molecules  Electronegativity Difference:  Description: Shares electrons evenly  Examples: H 2, CH 4, Cl 2, O 2, Br 2, I 2, etc.  They are generally gases at room temperature because they have little or † no attraction to other nonpolar molecules  Exceptions:  Bromine (Br 2 ) is a liquid (70 total electrons/molecule)  Iodine (I 2 ) is a solid (106 total electrons/molecule)  † A Temporary Dipoles can establish an attractive force if the molecules (1) get close enough and (2) are not moving fast.  Electronegativity Difference:  Description: Shares electrons evenly  Examples: H 2, CH 4, Cl 2, O 2, Br 2, I 2, etc.  They are generally gases at room temperature because they have little or † no attraction to other nonpolar molecules  Exceptions:  Bromine (Br 2 ) is a liquid (70 total electrons/molecule)  Iodine (I 2 ) is a solid (106 total electrons/molecule)  † A Temporary Dipoles can establish an attractive force if the molecules (1) get close enough and (2) are not moving fast.

Temporary Dipole

Polar Covalent Molecules  Electronegativity Difference:  Description: Shares electrons unevenly  Examples: H 2 O, NH 3  They are generally liquids or solids at room temperature because their permanent dipoles (slightly positive and slightly negative parts) attract their counterparts of other polar molecules and † many polar molecules are able to group together.  Example: Water Droplets  †  Electronegativity Difference:  Description: Shares electrons unevenly  Examples: H 2 O, NH 3  They are generally liquids or solids at room temperature because their permanent dipoles (slightly positive and slightly negative parts) attract their counterparts of other polar molecules and † many polar molecules are able to group together.  Example: Water Droplets  †

21.2 Electric Charge in the Atom Polar molecule: neutral overall, but charge not evenly distributed

Dipole-Dipole Bonding

Dipole-Dipole Bonds

Ionic Compounds (aka. Formula Units)  Electronegativity Difference: 1.66 and above  Description: “ † Transfers” electrons from one atom to another creating an attraction due to the charge of each atom.  Examples: NaCl, CaCl 2, MgO, KI, CuCl 2  They are solids at room temperature because their † permanent positive charges attract all other negative charges and a negative charge is attracted to all of the positive charges. This creates a large repeating structure known as a crystal lattice.  † In reality, the electron that has been transferred is still being attracted by the nucleus of the atom that has “lost” the electron, but the ratio of this attraction to the atom that has gained it is relatively small.  i.e. Cl - /Na + : 3.16/0.93 ≈ 3; The transferred electron is attracted 3 times more to the Cl ion than the Na ion.  Electronegativity Difference: 1.66 and above  Description: “ † Transfers” electrons from one atom to another creating an attraction due to the charge of each atom.  Examples: NaCl, CaCl 2, MgO, KI, CuCl 2  They are solids at room temperature because their † permanent positive charges attract all other negative charges and a negative charge is attracted to all of the positive charges. This creates a large repeating structure known as a crystal lattice.  † In reality, the electron that has been transferred is still being attracted by the nucleus of the atom that has “lost” the electron, but the ratio of this attraction to the atom that has gained it is relatively small.  i.e. Cl - /Na + : 3.16/0.93 ≈ 3; The transferred electron is attracted 3 times more to the Cl ion than the Na ion.

Crystal Lattice: NaCl

Summary  In regards to Electricity & Magnetism, write down:  3 things you already knew from today  2 things that you learned today  1 thing you would like to know  HW (Place in your agenda):  “Foundational Mathematics’ Skills of Physics” Packet (Page 1 & 2)  TEACHER HOMEWORK:  BUY MYLAR BALLOONS AND SCOTCH TAPE  In regards to Electricity & Magnetism, write down:  3 things you already knew from today  2 things that you learned today  1 thing you would like to know  HW (Place in your agenda):  “Foundational Mathematics’ Skills of Physics” Packet (Page 1 & 2)  TEACHER HOMEWORK:  BUY MYLAR BALLOONS AND SCOTCH TAPE

Friday (Day 3)

Warm-Up Fri, Jan 23  Identify the three bond types and their characteristics  Pickup a LAB JOURNAL from my desk.  Place your homework on my desk:  “Foundational Mathematics’ Skills of Physics” Packet (Page 1 & 2) Fri, Jan 23  Identify the three bond types and their characteristics  Pickup a LAB JOURNAL from my desk.  Place your homework on my desk:  “Foundational Mathematics’ Skills of Physics” Packet (Page 1 & 2)

Essential Question(s)  WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?  HOW DO WE DESCRIBE THE NATURE OF ELECTROSTATICS AND APPLY IT TO VARIOUS SITUATIONS?  How do we describe and apply the concept of electric field?  How do we compare and contrast the basic properties of an insulator and a conductor?  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we describe and apply Coulomb ’ s Law and the Principle of Superposition?  WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?  HOW DO WE DESCRIBE THE NATURE OF ELECTROSTATICS AND APPLY IT TO VARIOUS SITUATIONS?  How do we describe and apply the concept of electric field?  How do we compare and contrast the basic properties of an insulator and a conductor?  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we describe and apply Coulomb ’ s Law and the Principle of Superposition?

Vocabulary  Static Electricity  Electric Charge  Positive / Negative  Attraction / Repulsion  Charging / Discharging  Friction  Induction  Conduction  Law of Conservation of Electric Charge  Static Electricity  Electric Charge  Positive / Negative  Attraction / Repulsion  Charging / Discharging  Friction  Induction  Conduction  Law of Conservation of Electric Charge  Non-polar Molecules  Polar Molecules  Ion  Ionic Compounds  Force  Test Charge  Electric Field  Field Lines  Electric Dipole  Dipole Moment  Non-polar Molecules  Polar Molecules  Ion  Ionic Compounds  Force  Test Charge  Electric Field  Field Lines  Electric Dipole  Dipole Moment

Foundational Mathematics Skills in Physics Timeline DayPg(s)DayPg(s)DayPg(s)DayPg(s) † WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?

Agenda  Review “Foundational Mathematics’ Skills of Physics” Packet (Page 1 & 2) with answer guide in the back of the class  Introduction to Insulators and conductors  Begin Electrostatics Lab  Review “Foundational Mathematics’ Skills of Physics” Packet (Page 1 & 2) with answer guide in the back of the class  Introduction to Insulators and conductors  Begin Electrostatics Lab

Section 21.3  How do we compare and contrast the basic properties of an insulator and a conductor?  What are characteristics and classification(s) of electrically...  conductive atoms?  insulative atoms?  semi-conductive atoms?  conductive compounds?  insulative compounds?  semi-conductive compounds?  How do we compare and contrast the basic properties of an insulator and a conductor?  What are characteristics and classification(s) of electrically...  conductive atoms?  insulative atoms?  semi-conductive atoms?  conductive compounds?  insulative compounds?  semi-conductive compounds?

21.3 Insulators and Conductors Conductor: Charge flows freely Metals Insulator: Almost no charge flows Most other materials Some materials are semiconductors.

Why are certain atoms conductors and other insulators?  Recall on the periodic table that there are elements that do not react known as the Noble Gases. This is because their valence or outer energy levels contain 8 electrons ( † Helium only has 2 because it has only 1 energy level)  If possible other atoms on the periodic table will try to gain or lose electrons to acquire the same electron configurations as the Noble Gases.  Recall on the periodic table that there are elements that do not react known as the Noble Gases. This is because their valence or outer energy levels contain 8 electrons ( † Helium only has 2 because it has only 1 energy level)  If possible other atoms on the periodic table will try to gain or lose electrons to acquire the same electron configurations as the Noble Gases.

A Conductor or an Insulator?  Are the following elements conductors or insulators? Justify your answer.  Sodium  Chlorine  Oxygen  Potassium  Magnesium  Aluminum  Silicon  Are the following elements conductors or insulators? Justify your answer.  Sodium  Chlorine  Oxygen  Potassium  Magnesium  Aluminum  Silicon

Sodium is a conductor because it loses electrons easily.

Section 21.4  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we qualitatively explain the process of charging by induction?  How does an electroscope detect charge?  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we qualitatively explain the process of charging by induction?  How does an electroscope detect charge?

21.4 Induced Charge; the Electroscope Metal objects can be charged by conduction:

21.4 Induced Charge; the Electroscope They can also be charged by induction:

What does it mean to be “grounded“?  You must stay in the house for a week.  You have lost your privileges  You are in real trouble young man Or  You are firm in your belief of high morality.  You must stay in the house for a week.  You have lost your privileges  You are in real trouble young man Or  You are firm in your belief of high morality.

What does it mean to be “grounded“?  An object is said to be “grounded” or “earthed” when it is connected to a conducting wire or pipe leading into the ground.  Because the Earth is so large and can conduct electricity, it can easily accept or give up electrons. It is essentially a large reservoir or sink hole for (negative) electric charge (aka. electrons).  An object is said to be “grounded” or “earthed” when it is connected to a conducting wire or pipe leading into the ground.  Because the Earth is so large and can conduct electricity, it can easily accept or give up electrons. It is essentially a large reservoir or sink hole for (negative) electric charge (aka. electrons).

What would happen if...  a negatively-charged object were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the negatively-charged object was removed  after the negatively-charged object was removed  a negatively-charged object were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the negatively-charged object was removed  after the negatively-charged object was removed

What would happen if...  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a negatively-charged object were allowed to touch it...  and the negatively-charged object were then removed.  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a negatively-charged object were allowed to touch it...  and the negatively-charged object were then removed.

What would happen if...  a negatively-charged object were brought near a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the negatively-charged object was removed  after the negatively-charged object was removed  a negatively-charged object were brought near a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the negatively-charged object was removed  after the negatively-charged object was removed

What would happen if...  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a negatively-charged object were brought near it...  and the negatively-charged object were then removed.  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a negatively-charged object were brought near it...  and the negatively-charged object were then removed.

What would happen if...  a positively-charged object were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the positively-charged object was removed  after the positively-charged object was removed  a positively-charged object were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the positively-charged object was removed  after the positively-charged object was removed

What would happen if...  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a positively-charged object were allowed to touch it...  and the positively-charged object were then removed.  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a positively-charged object were allowed to touch it...  and the positively-charged object were then removed.

What would happen if...  a positively-charged object were brought near a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the positively-charged object was removed  after the positively-charged object was removed  a positively-charged object were brought near a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the positively-charged object was removed  after the positively-charged object was removed

What would happen if...  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a positively-charged object were brought near it...  and the positively-charged object were then removed.  a metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker and a positively-charged object were brought near it...  and the positively-charged object were then removed.

What would happen if...  a negatively-charged piece of plastic were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the negatively-charged piece of plastic was removed  after the negatively-charged piece of plastic was removed  a negatively-charged piece of plastic were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the negatively-charged piece of plastic was removed  after the negatively-charged piece of plastic was removed

What would happen if...  a positively-charged glass rod were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the positively-charged glass rod was removed  after the positively-charged glass rod was removed  a positively-charged glass rod were allowed to touch a...  metal faucet that was connected to ground and the pipe were chopped off with a super axe hacker...  before the positively-charged glass rod was removed  after the positively-charged glass rod was removed

Electrostatics Lab #1  5 Charge Stations  Density of Water  Graph: mass vs. volume  Calculate the slope  Water droplet/ml  #of water droplets on penny  Avogadro’s number  5 Charge Stations  Density of Water  Graph: mass vs. volume  Calculate the slope  Water droplet/ml  #of water droplets on penny  Avogadro’s number

Summary  Identify two differences between insulators and conductors  HW (Place in your agenda):  “Foundational Mathematics’ Skills of Physics” Packet (Page 13 & 14)  Identify two differences between insulators and conductors  HW (Place in your agenda):  “Foundational Mathematics’ Skills of Physics” Packet (Page 13 & 14)

Monday (Day 4)

Warm-Up Mon, Jan 26  Identify the charges on the  Amber rod  Fur  Glass Rod  Silk  Have you logged onto webassign.net?  Place your homework on my desk:  “Foundational Mathematics’ Skills of Physics” Packet (Page 13 & 14) Mon, Jan 26  Identify the charges on the  Amber rod  Fur  Glass Rod  Silk  Have you logged onto webassign.net?  Place your homework on my desk:  “Foundational Mathematics’ Skills of Physics” Packet (Page 13 & 14)

Essential Question(s)  WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?  HOW DO WE DESCRIBE THE NATURE OF ELECTROSTATICS AND APPLY IT TO VARIOUS SITUATIONS?  How do we describe and apply the concept of electric field?  How do we compare and contrast the basic properties of an insulator and a conductor?  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we describe and apply Coulomb ’ s Law and the Principle of Superposition?  WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?  HOW DO WE DESCRIBE THE NATURE OF ELECTROSTATICS AND APPLY IT TO VARIOUS SITUATIONS?  How do we describe and apply the concept of electric field?  How do we compare and contrast the basic properties of an insulator and a conductor?  How do we describe and apply the concept of induced charge and electrostatic shielding?  How do we describe and apply Coulomb ’ s Law and the Principle of Superposition?

Vocabulary  Static Electricity  Electric Charge  Positive / Negative  Attraction / Repulsion  Charging / Discharging  Friction  Induction  Conduction  Law of Conservation of Electric Charge  Static Electricity  Electric Charge  Positive / Negative  Attraction / Repulsion  Charging / Discharging  Friction  Induction  Conduction  Law of Conservation of Electric Charge  Non-polar Molecules  Polar Molecules  Ion  Ionic Compounds  Force  Test Charge  Electric Field  Field Lines  Electric Dipole  Dipole Moment  Non-polar Molecules  Polar Molecules  Ion  Ionic Compounds  Force  Test Charge  Electric Field  Field Lines  Electric Dipole  Dipole Moment

Foundational Mathematics Skills in Physics Timeline DayPg(s)DayPg(s)DayPg(s)DayPg(s) † WHAT PRIOR FOUNDATIONAL MATHEMATICS’ SKILLS ARE NECESSARY IN PHYSICS II?

Agenda  Review “Foundational Mathematics’ Skills of Physics” Packet (Page 13 & 14) with answer guide in the back of the class.  Discuss induction in insulators and electroscopes  Complete Electrostatics Lab #1 & 2  Review “Foundational Mathematics’ Skills of Physics” Packet (Page 13 & 14) with answer guide in the back of the class.  Discuss induction in insulators and electroscopes  Complete Electrostatics Lab #1 & 2

21.4 Induced Charge; the Electroscope Nonconductors won’t become charged by conduction or induction, but will experience charge separation:

Electron Cloud Polarization

Similar to the Temporary Dipole in I 2

21.4 Induced Charge; the Electroscope The electroscope can be used for detecting charge:

21.4 Induced Charge; the Electroscope The electroscope can be charged either by conduction or by induction.

21.4 Induced Charge; the Electroscope The charged electroscope can then be used to determine the sign of an unknown charge.

Summary  What happens to the electrons in an insulator during the process of “charging by” induction?  HW (Place in your agenda):  “Foundational Mathematics’ Skills of Physics” Packet (Page )  Electrostatics Lab #1: Lab Report (Due in 6 classes)  What happens to the electrons in an insulator during the process of “charging by” induction?  HW (Place in your agenda):  “Foundational Mathematics’ Skills of Physics” Packet (Page )  Electrostatics Lab #1: Lab Report (Due in 6 classes)