New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

PHY 184 Week 2 Notes- Electrostatics

by: Cameron Blochwitz

PHY 184 Week 2 Notes- Electrostatics PHY 184

Marketplace > Michigan State University > Physics > PHY 184 > PHY 184 Week 2 Notes Electrostatics
Cameron Blochwitz

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

In this set of notes I discuss the various topics that surround the electrostatic forces described by Coulomb's Law.
Physics for Scientists and Engineers II
Oscar Naviliat Cuncic
Class Notes
Physics, PHY184, Michigan State, Electrostatics, atoms, Polarization, coulomb's, Equilibrium
25 ?




Popular in Physics for Scientists and Engineers II

Popular in Physics

This 6 page Class Notes was uploaded by Cameron Blochwitz on Friday September 23, 2016. The Class Notes belongs to PHY 184 at Michigan State University taught by Oscar Naviliat Cuncic in Fall 2016. Since its upload, it has received 16 views. For similar materials see Physics for Scientists and Engineers II in Physics at Michigan State University.


Reviews for PHY 184 Week 2 Notes- Electrostatics


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 09/23/16
PHY 184 Lecture Notes Week 2 9/6-9/8 Electrostatics  Quark Structure of matter o Quarks are the smallest unit of matter  Atomic Structure  Atom  Nucleus  Nucleons  Quark  There are 6 different kinds of quarks +2 o Up/Charm/Top all have a charge of 3 e −1 o Down/Strange/Bottom all have a charge of 3 e  All matter is made up of these three elementary particles  Up/Down/Electron  Isolated quarks have never been observed  The carry a fractional charge Structure of an Atom  Atoms are neutrally charged o Composed of a positive nucleus and negative electrons  Nucleus itself is made of positive protons and neutral neutrons Describing an Atom  Atomic Number (Z): Number of Protons or Electrons  Mass Number (A): Number of Nucleons (Protons and Electrons)  Number of Electrons: equal to Z, charge -Ze  Number of Protons: equal to Z, Charge Ze  Number of Neutrons N: A-Z=N  Atomic Mass: Z*M +p*M n Electrons and Protons  Electron is an elementary particle o It cannot be further subdivided  Proton is not an elementary particle o Composed of 2 Up Quarks and 1 Down Quark o Charge of a Proton 2 2 1  qp=3e+3 e−3e=e Up Up Down  Neutron is not an elementary particle o Composed of 2 Down Quarks and 1 Down Quark o Charge of a Proton n = e− e− e=0  3 3 3 UP Dow n Down  Quarks are held together by the strong force  Electric charge is a fundamental property that a particle or object must have in order to experience any electromagnetic interaction o Without charge the object cannot interact with electromagnetic fields.  There are 2 main kinds of charges positive and negative  Charged Rods Demonstration o Rubbing the rods will charge them  Like charges will repel each other  Opposite charges will attract each other  Unit of charge is the Coulomb, C o Defined in terms of the Ampere  1 C = 1 A*s (Ampere Second)  Unit Charge is defined by the electron o qe=−e −19 o e=1.602×10 C o Proton carries a charge of +e  1 C is a very large amount of charge o Often will be using smaller charges −6  1 μC = 1×10 C 1×10 −9  1 nC = C 1×10−12  1 pC = C  Number of Electons to produce 1 C 1C N e −19 o 1.602×10 C  The electric charge is quantized o There is a minimum amount of charge a particle can have  This charge is e  This is too small to be noticed in daily life  But the Quarks have fractional charges! o This is possible because quarks are never isolated  They are unable to exist on their own  Charges of macroscopic objects are neutral o If it carries a negative it has extra electrons o If it carries a positive charge it is missing electrons  ONLY ELECTRONS MOVE!!!  Charges are able to be moved around o They can never be created o In any process the net charge is always a constant  The electron structure of materials determines their ability to conduct electricity o Conductors conduct very well o Insulators conduct very poorly Electric Forces by Polarization  Demonstration (Rotating Rod/Hanging Insulator) o There is an electric force between a charged rod and an uncharged one  Why does this occur o The charged rod induces polarization it attracts the electrons and produces a net force + + + + + + + + + + + + - + + + + + + + + + + - 2 Point Charges  Consider a single point charge q 1  Add a second point charge q 2 r q2  We can use Coulomb’s Law to find the force q1q2  F 1→2k 2 ^ r  k is known as Coulomb’s constant 9N m2  8.99×10 2 C  r^ is a unit vector pointing from q to 1 2 o This direction is fixed; the direction of the force will be determined by the signs on the charges o k and r are always positive  Signs of charge are opposite the attract  Signs of charge are the same they repel  Coulomb’s Law contains the Law of Charges Comparing Electromagnetism and Gravity qe m e  F ek 2 F gG 2 r r  r will cancel and so 2 2  F ekq e F gG m e F e 42  =4.20×10 F g  The electric interaction is vastly stronger than gravity o So much stronger that we are able to ignore gravity System of Charges  When working with a system of charges you will need to consider each interaction of all the charges  The force from system of charges (q , q , … , q 1 on2Q is n q1 q2 qn r r^1+r r^2+…+ r ^n o 1 2 n F=kQ¿ o This is known as the superposition principle  It shows a vector sum of forces Equilibrium Position  Two positive charges q and q are1placed a2 shown, where will a third charge q keep the system in equilibrium 3 o We know that the F 1 on 3must be equal to F 2 on 3 o When added the forces net to zero. o We therefore have the equation q q 1 = 2  (x −x ) 2 (x −x ) 2 3 1 2 3  Solve for x 3  Note the charge of q is irrele3ant!  This method is the basis for all equilibrium problems


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Anthony Lee UC Santa Barbara

"I bought an awesome study guide, which helped me get an A in my Math 34B class this quarter!"

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.