Chapter Sixteen: Electric Charge and Electric Fields
|
|
- Randolph Malone
- 5 years ago
- Views:
Transcription
1 Chapte Sixteen: Electic Chage and Electic Fields Key Tems Chage Conducto The fundamental electical popety to which the mutual attactions o epulsions between electons and potons ae attibuted. Any mateial though which heat and o electical chage can be tansfeed. Mateials, usually metals, though which electons can flow. Good conductos of heat ae geneally good conductos of electicity. Consevation of Chage The pinciple that electic chage is neithe ceated no destoyed but it tansfeable fom one mateial to anothe. Coulomb Coulomb s Law Electical Foce SI unit of chage. One coulomb (symbol C) is equal to the total chage of electons. The elationship between electical foce, chages, and distance: The electical foce between two chages vaies diectly as the poduct of the chages and invesely as the squae of the distance between them. A foce that one chage exets on anothe. When the chages ae the same sign, they epel; when the chages ae opposite, they attact. Electically Polaised Tem applied to an atom o molecule in which the chages ae sepaated so that one side is slightly moe positive o negative than the opposite side. Electostatics The study of electic chages at est. Eathing / Gounding Allowing chages to move feely along a connection between a conducto and the gound o eath. Induction of Chage Insulato Supeconducto Electic Field The chaging of an object without diect contact with anothe chaged body. A mateial that is a poo conducto of heat and also a mateial that is a poo conducto of electicity. Mateial that has infinite conductivity at vey low tempeatues, so that chage flows though it without esistance. exists in a space suounding a chaged paticle o object. Electic fields ae epesented by lines of foce that stat on a positive chage and end on a negative chage. (Measued by foce/chage - N/C), Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page of
2 Electostatics Electostatics is concened with electic chages at est. Concept of the Atom Potons Neutons Electons Chage Neutons Positive cental nucleus (no chage) Nucleus suounded by negatively chaged electons. Potons Nucleus composed of potons and (positive chage) neutons. Electons Mass of poton 000 time mass of an (negative chage) electon. Neuton slightly moe massive than a poton. - positively chaged - no chage - negatively chaged Lie chages Repel Unlie chages Attact Chage is the electical popety to which the attaction and epulsion of potons and electons is attibuted. Chage is measued in coulombs (C). Fo example an electon has a chage of C. Consevation of Chage The outemost electons ae loosely bound to the atom and ae elatively easily dislodged. Hence when thee is fiction (ubbing), thee is a tansfe of electons. An imbalance of electons esults in a net electic chage. An excess of electons yields a net negative chage. A deficiency of electons yields a net positive chage. Electons ae not ceated o destoyed, they ae simply tansfeed. Chage is conseved. Conductos have vey loosely bound electons Sea of Electons which ae in a lattice of positive ions. eg. metals. Insulatos have tightly bound electons that emain with paticula atoms. eg. plastics, ubbe., Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page of
3 Coulomb s Law F Recall Newton s Law of Gavitation whee G is the univesal gavitational constant. This foce is attactive and along the line joining the two point masses m and m. The electical foce between any two objects obeys a simila invese-squae elationship with distance. Coulomb s Law states that fo chaged paticles the foce between the chages vaies diectly as the poduct of the chages and invesely as the squae of the distance between them. F whee epesents the chage of one paticle epesents the chage of the othe paticle d is the distance between the chage paticles. popotionality constant Nm /C (SI units) 4 πε 0 (ε 0 pemittivity of fee space) Note: Fee space is consideed to be a vacuum. The value of the constant of pemittivity is only slightly diffeent in ai and we shall ignoe this diffeence. This equation gives the magnitude of the electic foce that eithe object exets on the othe, when the magnitudes of the chages and ae given. The diection of the electic foce is always along the line joining the two chaged paticles. If two chages have: same sign opposite sign d G m d the foce on eithe object is diected away fom the othe. ie. epulsion occus. foce on one is diected towads the othe. ie. attaction occus. m, Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 3 of
4 Note that the foce the fist chage exets on the second is equal but opposite to that exeted by the second on the fist (Newton s Thid Law). Note: Coulomb s Law equation gives the foce on a chage due to only one othe chage. If seveal (o many) chages ae pesent, the net foce on any one of them will be the vecto sum of the foces due to each of the othes (Electic foces add as vectos). This is sometimes efeed to as the pinciple of supeposition of foces. F F + F +... net n F n The magnitude of the foce can be calculated using Coulomb s Law. The diection is along the line joining the chages (attaction o epulsion depending on the natue of the chages: lie chages epel, unlie attact). Thee Chages in a Line (This comes diectly fom Example 6-3 in ) Thee chaged paticles ae aanged in a line, as shown. Calculate the net electostatic foce on paticle 3 (-4.0µC) due to the othe two chages. Solution The net foce on paticle 3 will be the vecto sum of the foce F 3 exeted by paticle and the foce F 3 exeted by paticle : F F 3 + F 3. The magnitudes of these two foces ae: F F 3 3 ( ( Nm Nm /C /C )( ( 0. 50m) )( ( 0. 0 m) 6 6 C)( C)( C) C). N. 7N, Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 4 of
5 Since we wee calculating the magnitudes of the foces, we omitted the signs of the chages; but we must be awae of them to get the diection of each foce. Let the line joining the paticles be the x-axis, and we tae it positive to the ight. Then, because F 3 is epulsive and F 3 is attactive, the diections of the foces ae as shown below: F 3 points in the positive x diection and F 3 points in the negative x diection. The net foce on paticle 3 is then F 3 F3 + F. 7 N +. N. 5N The magnitude of the net foce is.5n, and it points to the left. Electic Field Contact Foce Foce Field is a common foce whee contact is made by a push o pull. eg. pushing a ca o hitting a softball. is a concept of a foce acting at a distance. Both gavitational and electical foce act at a distance. The space is said to contain a foce field theefoe the mass o chage is in contact (inteacts) with the field all the time. An electic field suounds evey chaged body in space. When a second chage is placed nea the fist chage, it feels a foce because of this electic field. We can investigate the electic field suounding a chage o a goup of chages by measuing the foce on a small positive test chage. Electic field is defined in tems of the foce on a small positive test chage. E (Electic Field) F (foce) q (foce pe unit chage) (Newtons/Coulomb) diection is the diection of the foce on a small positive test chage. E is a vecto quantity., Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 5 of
6 The electic field due to a single point chage can be witten (whee q is a small positive test chage placed at a distance fom chage ) E F q q q 4 πε Electic Field of a Single Point Chage (This comes diectly fom Example 6-6 in ) Calculate the magnitude and diection of the electic field at a point P which is 30cm to the ight of a point chage C. Solution The magnitude of the electic field due to a single point chage is given by: E 9 6 ( Nm /C )( C ) ( m ) The diection of the electic field is towad the chage as shown in (a) below since we defined the diection as that of the foce on a positive test chage. If had been positive, the electic field would have pointed away, as in shown in (b) below. If the field is due to moe than one chage, the individual electic fields (E, E, ) due to each chage ae added vectoially to get the total field at any point (supeposition pinciple). E E E N/C, Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 6 of
7 E at a Position Between Two Point Chages (This comes diectly fom Example 6-7 in ) Two point chages ae sepaated by a distance of 0.0cm. One has a chage of - 5µC and the othe +50µC. (a) What is the diection and magnitude of the electic field at a point P in between them, that is.0cm fom the negative chage? The field will be a vecto sum of two fields both pointing to the left: the field due to the negative chage points towad, and the field due to the positive chage points away fom, again to the left. Thus we can add the magnitudes of the two fields togethe algebaically, ignoing the signs of the chages: E whee in the last step we factoed out ( / ). We substitute in.0cm m and m: E ( ) ( ( ) ) C 9 0 Nm C m [ + ] NC NC 8 + ( 50 5) ( ) Notice how factoing out / on the fist line allowed us to see the elative stengths of the two contibuting fields, namely that s field is only / 8 of s (o / 9 of the total). (b) If an electon is placed at est at P, what will its acceleation a be? Give both magnitude and diection fo a. The electon will feel a foce to the ight since it is negatively chaged and the acceleation will theefoe be to the ight, with a magnitude of: Note: 9 8 ( C)( NC ) 0 F qe a. 0 3 m m 9. 0 g If we ae given the electic field E at a given point in space then we can calculate the foce F on a chage q: F q E ms, Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 7 of
8 Electic Field Lines (Line of Foce) A seies of lines ae dawn to indicate the diection of the electic field at vaious points in space. Each line epesents the diection of the electic field. Only a few epesentative lines ae dawn. The close the lines ae togethe, the stonge the electic field in that egion. If the field line is cuved, E is epesented by a tangent to that cuve. Electic field lines stat on positive chages and end on negative chages. The field lines between chaged paallel plates ae equally spaced (except nea the edges) so E has the same magnitude at all points (Econstant)., Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 8 of
9 Electic Fields and Conductos The electic field inside a hollow conducto is exactly zeo, even if it is chaged. If the metal sphee is chaged, because of mutual epulsion, the electons have spead as fa apat as possible and distibute themselves unifomly ove the suface of the sphee. The foces on a positive test chage located inside a chaged hollow sphee cancel to zeo. If the conducto is not spheical, then the chage distibution will not be unifom. Fo example, in a cube most of the chage is located nea the cones. The exact chage distibution ove the sufaces and cones of all hollow conductos is such that the electic field eveywhee inside the conducto is zeo. On an iegula shaped conducto, the chage tends to accumulate at locations whee the adius of cuvatue of suface is smallest (at the shap points o edges). Static chages ae distibuted on the suface of all conductos in such a way that the electic field inside the conductos is zeo The electic field outside a conducto is always pependicula to the suface at any point., Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 9 of
10 APPLICATION: PHOTOCOPIER Photocopies and lase pintes employ simila pinciples and povide a vey good example of the application of electic fields. They ae devices that pint copies of documents, dawings etc fom an optical image to a sheet of copy pape. Ionisation of the ai by electic fields. When the ai is exposed to an electic field, the (few) ions, which natually occu in the ai, ae acceleated in the diection of the field until they collide with neutal gas molecules. If the electic field is lage enough then the ions will have sufficient enegy to ionise the molecules, poducing additional ions and electons. The esultant chaged paticles ae then acceleated and collide with othe neutal molecules theeby poducing moe ionisation. Coona Dischage Electic fields lage enough to ionise the ai can be poduced using a shap point, o by applying a high voltage lage than seveal V to a smalle wie as in a photocopie. Shap points ae commonly used as lightning ods to emove the chaged paticles fom the ai and thus pevent the lightning fom stiing the object to which the od is attached. A Coona Dischage can be poduced by sticing a needle onto the dome of a Van de Gaaff geneato. The flow of ions (fom the point) can be seen to deflect a candle flame o a piece of pape held vetically., Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page 0 of
11 A Coona Dischage is a esult of a net movement of many positively and negatively chaged paticles in opposite diection to the electic field. (+ve tavel in same diection as E and -ve tavel in opposite diection to E) Non-conducting (often called dielectics) mateials, ae polaised when placed in electic field ie individual paticles loo lie diagams below: No field E- Field (diection ) Thee is a sepaation of chage in paticles when E is vey high, the ve chages (electons) and the +ve chaged ions ae sepaated and then the mateial (solid, liquid o gas) becomes ionised. Recombination and othe chemical pocesses occu esulting in enegy being given out, often in the fom of heat, light o sound. The light is bluish o eddish depending on the ions pesent and a coloued luminous glow suounds the conducto called a Coona Dischage. A Photoconductive Suface is a mateial that is a poo conducto of electicity in the da but becomes a easonably good conducto when exposed to light. THE PROCESS: The photoconductive suface is given a positive electostatic chage in the da. A thin coona wie, which extends ove the full length of a dum and chages the photoconductive suface placed on this dum do this. The chage is positive and distibuted unifomly as the dum otates unde the wie. The page to be copied is then pojected onto the chaged suface. The photoconducting suface becomes conducting only in aeas whee the light sties (ie whee the light poduces chage caies on the photoconductive suface theefoe neutalising the positive chages suface.) Since the chages emain on those egions of the photoconductive suface not exposed to the light a hidden image of the object is now in the fom of a positive suface chage distibution. This suface is then coveed with a negatively chaged powde, a tone, which adhees only to the positively chaged image aea. This image is then tansfeed to the suface of a sheet of pape, which is positively chaged and then finally fixed by heat (melted). This then povides a pemanent copy of the oiginal.. Conside Summay (p.496). Sample uestions Activities 3. uestions (p.496,497: no.5, 9, 0, 9) 4. Poblems (p.497,498: no.,, 3, 5, 6, 7,, 3, 4, 5), Physics, 5 th Edition Chapte Sixteen: Electic Chage & Electic Fields Page of
Lecture 3.7 ELECTRICITY. Electric charge Coulomb s law Electric field
Lectue 3.7 ELECTRICITY Electic chage Coulomb s law Electic field ELECTRICITY Inteaction between electically chages objects Many impotant uses Light Heat Rail tavel Computes Cental nevous system Human body
More information20-9 ELECTRIC FIELD LINES 20-9 ELECTRIC POTENTIAL. Answers to the Conceptual Questions. Chapter 20 Electricity 241
Chapte 0 Electicity 41 0-9 ELECTRIC IELD LINES Goals Illustate the concept of electic field lines. Content The electic field can be symbolized by lines of foce thoughout space. The electic field is stonge
More informationPhysics 11 Chapter 20: Electric Fields and Forces
Physics Chapte 0: Electic Fields and Foces Yesteday is not ous to ecove, but tomoow is ous to win o lose. Lyndon B. Johnson When I am anxious it is because I am living in the futue. When I am depessed
More informationElectrostatics. 3) positive object: lack of electrons negative object: excess of electrons
Electostatics IB 12 1) electic chage: 2 types of electic chage: positive and negative 2) chaging by fiction: tansfe of electons fom one object to anothe 3) positive object: lack of electons negative object:
More informationPhysics 107 TUTORIAL ASSIGNMENT #8
Physics 07 TUTORIAL ASSIGNMENT #8 Cutnell & Johnson, 7 th edition Chapte 8: Poblems 5,, 3, 39, 76 Chapte 9: Poblems 9, 0, 4, 5, 6 Chapte 8 5 Inteactive Solution 8.5 povides a model fo solving this type
More informationElectricity Revision ELECTRICITY REVISION KEY CONCEPTS TERMINOLOGY & DEFINITION. Physical Sciences X-Sheets
Electicity Revision KEY CONCEPTS In this session we will focus on the following: Stating and apply Coulomb s Law. Defining electical field stength and applying the deived equations. Dawing electical field
More information17.1 Electric Potential Energy. Equipotential Lines. PE = energy associated with an arrangement of objects that exert forces on each other
Electic Potential Enegy, PE Units: Joules Electic Potential, Units: olts 17.1 Electic Potential Enegy Electic foce is a consevative foce and so we can assign an electic potential enegy (PE) to the system
More informationChapter 22: Electric Fields. 22-1: What is physics? General physics II (22102) Dr. Iyad SAADEDDIN. 22-2: The Electric Field (E)
Geneal physics II (10) D. Iyad D. Iyad Chapte : lectic Fields In this chapte we will cove The lectic Field lectic Field Lines -: The lectic Field () lectic field exists in a egion of space suounding a
More information7.2. Coulomb s Law. The Electric Force
Coulomb s aw Recall that chaged objects attact some objects and epel othes at a distance, without making any contact with those objects Electic foce,, o the foce acting between two chaged objects, is somewhat
More informationPHYS 1441 Section 002. Lecture #3
PHYS 1441 Section 00 Chapte 1 Lectue #3 Wednesday, Sept. 6, 017 Coulomb s Law The Electic Field & Field Lines Electic Fields and Conductos Motion of a Chaged Paticle in an Electic Field Electic Dipoles
More informationElectrostatics (Electric Charges and Field) #2 2010
Electic Field: The concept of electic field explains the action at a distance foce between two chaged paticles. Evey chage poduces a field aound it so that any othe chaged paticle expeiences a foce when
More informationCHAPTER 10 ELECTRIC POTENTIAL AND CAPACITANCE
CHAPTER 0 ELECTRIC POTENTIAL AND CAPACITANCE ELECTRIC POTENTIAL AND CAPACITANCE 7 0. ELECTRIC POTENTIAL ENERGY Conside a chaged paticle of chage in a egion of an electic field E. This filed exets an electic
More informationCharges, Coulomb s Law, and Electric Fields
Q&E -1 Chages, Coulomb s Law, and Electic ields Some expeimental facts: Expeimental fact 1: Electic chage comes in two types, which we call (+) and (). An atom consists of a heavy (+) chaged nucleus suounded
More informationPotential Energy. The change U in the potential energy. is defined to equal to the negative of the work. done by a conservative force
Potential negy The change U in the potential enegy is defined to equal to the negative of the wok done by a consevative foce duing the shift fom an initial to a final state. U = U U = W F c = F c d Potential
More informationObjectives: After finishing this unit you should be able to:
lectic Field 7 Objectives: Afte finishing this unit you should be able to: Define the electic field and explain what detemines its magnitude and diection. Wite and apply fomulas fo the electic field intensity
More informationElectric Field. y s +q. Point charge: Uniformly charged sphere: Dipole: for r>>s :! ! E = 1. q 1 r 2 ˆr. E sphere. at <0,r,0> at <0,0,r>
Electic Field Point chage: E " ˆ Unifomly chaged sphee: E sphee E sphee " Q ˆ fo >R (outside) fo >s : E " s 3,, at z y s + x Dipole moment: p s E E s "#,, 3 s "#,, 3 at
More informationCHAPTER 25 ELECTRIC POTENTIAL
CHPTE 5 ELECTIC POTENTIL Potential Diffeence and Electic Potential Conside a chaged paticle of chage in a egion of an electic field E. This filed exets an electic foce on the paticle given by F=E. When
More informationUNIT 3:Electrostatics
The study of electic chages at est, the foces between them and the electic fields associated with them. UNIT 3:lectostatics S7 3. lectic Chages and Consevation of chages The electic chage has the following
More informationAlgebra-based Physics II
lgebabased Physics II Chapte 19 Electic potential enegy & The Electic potential Why enegy is stoed in an electic field? How to descibe an field fom enegetic point of view? Class Website: Natual way of
More information18.1 Origin of Electricity 18.2 Charged Objects and Electric Force
1 18.1 Oigin of lecticity 18. Chaged Objects and lectic Foce Thee ae two kinds of electic chage: positive and negative. The SI unit of electic chage is the coulomb (C). The magnitude of the chage on an
More informationChapter 4. Newton s Laws of Motion
Chapte 4 Newton s Laws of Motion 4.1 Foces and Inteactions A foce is a push o a pull. It is that which causes an object to acceleate. The unit of foce in the metic system is the Newton. Foce is a vecto
More informationReview. Electrostatic. Dr. Ray Kwok SJSU
Review Electostatic D. Ray Kwok SJSU Paty Balloons Coulomb s Law F e q q k 1 Coulomb foce o electical foce. (vecto) Be caeful on detemining the sign & diection. k 9 10 9 (N m / C ) k 1 4πε o k is the Coulomb
More informationObjects usually are charged up through the transfer of electrons from one object to the other.
1 Pat 1: Electic Foce 1.1: Review of Vectos Review you vectos! You should know how to convet fom pola fom to component fom and vice vesa add and subtact vectos multiply vectos by scalas Find the esultant
More information(r) = 1. Example: Electric Potential Energy. Summary. Potential due to a Group of Point Charges 9/10/12 1 R V(r) + + V(r) kq. Chapter 23.
Eample: Electic Potential Enegy What is the change in electical potential enegy of a eleased electon in the atmosphee when the electostatic foce fom the nea Eath s electic field (diected downwad) causes
More informationElectric Charge and Field
lectic Chage and ield Chapte 6 (Giancoli) All sections ecept 6.0 (Gauss s law) Compaison between the lectic and the Gavitational foces Both have long ange, The electic chage of an object plas the same
More informationFlux. Area Vector. Flux of Electric Field. Gauss s Law
Gauss s Law Flux Flux in Physics is used to two distinct ways. The fist meaning is the ate of flow, such as the amount of wate flowing in a ive, i.e. volume pe unit aea pe unit time. O, fo light, it is
More information2. Electrostatics. Dr. Rakhesh Singh Kshetrimayum 8/11/ Electromagnetic Field Theory by R. S. Kshetrimayum
2. Electostatics D. Rakhesh Singh Kshetimayum 1 2.1 Intoduction In this chapte, we will study how to find the electostatic fields fo vaious cases? fo symmetic known chage distibution fo un-symmetic known
More information! E da = 4πkQ enc, has E under the integral sign, so it is not ordinarily an
Physics 142 Electostatics 2 Page 1 Electostatics 2 Electicity is just oganized lightning. Geoge Calin A tick that sometimes woks: calculating E fom Gauss s law Gauss s law,! E da = 4πkQ enc, has E unde
More informationPHYSICS 151 Notes for Online Lecture #36
Electomagnetism PHYSICS 151 Notes fo Online Lectue #36 Thee ae fou fundamental foces in natue: 1) gavity ) weak nuclea 3) electomagnetic 4) stong nuclea The latte two opeate within the nucleus of an atom
More informationLook over Chapter 22 sections 1-8 Examples 2, 4, 5, Look over Chapter 16 sections 7-9 examples 6, 7, 8, 9. Things To Know 1/22/2008 PHYS 2212
PHYS 1 Look ove Chapte sections 1-8 xamples, 4, 5, PHYS 111 Look ove Chapte 16 sections 7-9 examples 6, 7, 8, 9 Things To Know 1) What is an lectic field. ) How to calculate the electic field fo a point
More informationELECTROSTATICS::BHSEC MCQ 1. A. B. C. D.
ELETROSTATIS::BHSE 9-4 MQ. A moving electic chage poduces A. electic field only. B. magnetic field only.. both electic field and magnetic field. D. neithe of these two fields.. both electic field and magnetic
More informationEM-2. 1 Coulomb s law, electric field, potential field, superposition q. Electric field of a point charge (1)
EM- Coulomb s law, electic field, potential field, supeposition q ' Electic field of a point chage ( ') E( ) kq, whee k / 4 () ' Foce of q on a test chage e at position is ee( ) Electic potential O kq
More informationChapter 21: Gauss s Law
Chapte : Gauss s Law Gauss s law : intoduction The total electic flux though a closed suface is equal to the total (net) electic chage inside the suface divided by ε Gauss s law is equivalent to Coulomb
More informationPhysics 2B Chapter 22 Notes - Magnetic Field Spring 2018
Physics B Chapte Notes - Magnetic Field Sping 018 Magnetic Field fom a Long Staight Cuent-Caying Wie In Chapte 11 we looked at Isaac Newton s Law of Gavitation, which established that a gavitational field
More informationPhysics 2212 GH Quiz #2 Solutions Spring 2016
Physics 2212 GH Quiz #2 Solutions Sping 216 I. 17 points) Thee point chages, each caying a chage Q = +6. nc, ae placed on an equilateal tiangle of side length = 3. mm. An additional point chage, caying
More informationIntroduction: Vectors and Integrals
Intoduction: Vectos and Integals Vectos a Vectos ae chaacteized by two paametes: length (magnitude) diection a These vectos ae the same Sum of the vectos: a b a a b b a b a b a Vectos Sum of the vectos:
More information? this lecture. ? next lecture. What we have learned so far. a Q E F = q E a. F = q v B a. a Q in motion B. db/dt E. de/dt B.
PHY 249 Lectue Notes Chapte 32: Page 1 of 12 What we have leaned so fa a a F q a a in motion F q v a a d/ Ae thee othe "static" chages that can make -field? this lectue d/? next lectue da dl Cuve Cuve
More informationElectric Forces: Coulomb s Law
Electic Foces: Coulomb s Law All the matte aound you contains chaged paticles, and it is the electic foces between these chaged paticles that detemine the stength of the mateials and the popeties of the
More informationThe Electric Field. Electric Charge HAPTER Historical Origins
C HAPTER17 The Electic Field Y This electical dischage was poduced at the tun of the 0th centuy by invento Nikola Tesla, shown in the photo. ou can obseve static electicity in vaious ways. Walk acoss a
More informationPY208 Matter & Interactions Final Exam S2005
PY Matte & Inteactions Final Exam S2005 Name (pint) Please cicle you lectue section below: 003 (Ramakishnan 11:20 AM) 004 (Clake 1:30 PM) 005 (Chabay 2:35 PM) When you tun in the test, including the fomula
More informationBetween any two masses, there exists a mutual attractive force.
YEAR 12 PHYSICS: GRAVITATION PAST EXAM QUESTIONS Name: QUESTION 1 (1995 EXAM) (a) State Newton s Univesal Law of Gavitation in wods Between any two masses, thee exists a mutual attactive foce. This foce
More informationPhysics 202, Lecture 2
Physics 202, Lectue 2 Todays Topics Electic Foce and Electic Fields Electic Chages and Electic Foces Coulomb's Law Physical Field The Electic Field Electic Field Lines Motion of Chaged Paticle in Electic
More informationGauss Law. Physics 231 Lecture 2-1
Gauss Law Physics 31 Lectue -1 lectic Field Lines The numbe of field lines, also known as lines of foce, ae elated to stength of the electic field Moe appopiately it is the numbe of field lines cossing
More informationThe Millikan Experiment: Determining the Elementary Charge
LAB EXERCISE 7.5.1 7.5 The Elementay Chage (p. 374) Can you think of a method that could be used to suggest that an elementay chage exists? Figue 1 Robet Millikan (1868 1953) m + q V b The Millikan Expeiment:
More informationChapter 13 Gravitation
Chapte 13 Gavitation In this chapte we will exploe the following topics: -Newton s law of gavitation, which descibes the attactive foce between two point masses and its application to extended objects
More informationElectric Field, Potential Energy, & Voltage
Slide 1 / 66 lectic Field, Potential negy, & oltage Wok Slide 2 / 66 Q+ Q+ The foce changes as chages move towads each othe since the foce depends on the distance between the chages. s these two chages
More informationTo Feel a Force Chapter 7 Static equilibrium - torque and friction
To eel a oce Chapte 7 Chapte 7: Static fiction, toque and static equilibium A. Review of foce vectos Between the eath and a small mass, gavitational foces of equal magnitude and opposite diection act on
More informationAP Physics - Coulomb's Law
AP Physics - oulomb's Law We ve leaned that electons have a minus one chage and potons have a positive one chage. This plus and minus one business doesn t wok vey well when we go in and ty to do the old
More informationDEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS
DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS TSOKOS LESSON 10-1 DESCRIBING FIELDS Essential Idea: Electic chages and masses each influence the space aound them and that influence can be epesented
More informationClass 2. Lesson 1 Stationary Point Charges and Their Forces. Basic Rules of Electrostatics. Basic Rules of Electrostatics
Lesson 1 Stationay Point Chages and Thei Foces Class Today we will: lean the basic chaacteistics o the electostatic oce eview the popeties o conductos and insulatos lean what is meant by electostatic induction
More informationChapter 20 Electrostatics and Coulomb s Law 20.1 Introduction electrostatics Separation of Electric Charge by Rubbing
I wish to give an account of some investigations which have led to the conclusion that the caies of negative electicity ae bodies, which I have called copuscles, having a mass vey much smalle than that
More informationGeneral Physics (PHY 2140)
Geneal Physics (PHY 140) Intoduction Syllabus and teaching stategy lecticity and Magnetism Popeties of electic chages Insulatos and conductos oulomb s law Lectue: Office Hous: D. Alan A. Sebastian, Physics
More informationPHYS 1444 Lecture #5
Shot eview Chapte 24 PHYS 1444 Lectue #5 Tuesday June 19, 212 D. Andew Bandt Capacitos and Capacitance 1 Coulom s Law The Fomula QQ Q Q F 1 2 1 2 Fomula 2 2 F k A vecto quantity. Newtons Diection of electic
More informationanubhavclasses.wordpress.com CBSE Solved Test Papers PHYSICS Class XII Chapter : Electrostatics
CBS Solved Test Papes PHYSICS Class XII Chapte : lectostatics CBS TST PAPR-01 CLASS - XII PHYSICS (Unit lectostatics) 1. Show does the foce between two point chages change if the dielectic constant of
More informationChapter 23: GAUSS LAW 343
Chapte 23: GAUSS LAW 1 A total chage of 63 10 8 C is distibuted unifomly thoughout a 27-cm adius sphee The volume chage density is: A 37 10 7 C/m 3 B 69 10 6 C/m 3 C 69 10 6 C/m 2 D 25 10 4 C/m 3 76 10
More informationPhys102 Second Major-182 Zero Version Monday, March 25, 2019 Page: 1
Monday, Mach 5, 019 Page: 1 Q1. Figue 1 shows thee pais of identical conducting sphees that ae to be touched togethe and then sepaated. The initial chages on them befoe the touch ae indicated. Rank the
More informationAP Physics Electric Potential Energy
AP Physics lectic Potential negy Review of some vital peviously coveed mateial. The impotance of the ealie concepts will be made clea as we poceed. Wok takes place when a foce acts ove a distance. W F
More informationElectromagnetism Physics 15b
lectomagnetism Physics 15b Lectue #20 Dielectics lectic Dipoles Pucell 10.1 10.6 What We Did Last Time Plane wave solutions of Maxwell s equations = 0 sin(k ωt) B = B 0 sin(k ωt) ω = kc, 0 = B, 0 ˆk =
More informationPHYSICS 272 Electric & Magnetic Interactions
PHYS 7: Matte and Inteactions II -- Electic And Magnetic Inteactions http://www.physics.pudue.edu/academic_pogams/couses/phys7/ PHYSICS 7 Electic & Magnetic Inteactions Lectue 3 Chaged Objects; Polaization
More informationOn the Sun s Electric-Field
On the Sun s Electic-Field D. E. Scott, Ph.D. (EE) Intoduction Most investigatos who ae sympathetic to the Electic Sun Model have come to agee that the Sun is a body that acts much like a esisto with a
More informationPearson Physics Level 30 Unit VI Forces and Fields: Unit VI Review Solutions
Peason Physics Level 30 Unit VI Foces and Fields: Unit VI Review Solutions Student Book pages 66 631 Vocabulay 1. ampee: the flow of 1 C of chage past a point in a conducto in 1 s chage migation: movement
More information(Sample 3) Exam 1 - Physics Patel SPRING 1998 FORM CODE - A (solution key at end of exam)
(Sample 3) Exam 1 - Physics 202 - Patel SPRING 1998 FORM CODE - A (solution key at end of exam) Be sue to fill in you student numbe and FORM lette (A, B, C) on you answe sheet. If you foget to include
More informationChapter 5 Force and Motion
Chapte 5 Foce and Motion In Chaptes 2 and 4 we have studied kinematics, i.e., we descibed the motion of objects using paametes such as the position vecto, velocity, and acceleation without any insights
More informationChapter 5 Force and Motion
Chapte 5 Foce and Motion In chaptes 2 and 4 we have studied kinematics i.e. descibed the motion of objects using paametes such as the position vecto, velocity and acceleation without any insights as to
More information15 B1 1. Figure 1. At what speed would the car have to travel for resonant oscillations to occur? Comment on your answer.
Kiangsu-Chekiang College (Shatin) F:EasteHolidaysAssignmentAns.doc Easte Holidays Assignment Answe Fom 6B Subject: Physics. (a) State the conditions fo a body to undego simple hamonic motion. ( mak) (a)
More informationm1 m2 M 2 = M -1 L 3 T -2
GAVITATION Newton s Univesal law of gavitation. Evey paticle of matte in this univese attacts evey othe paticle with a foce which vaies diectly as the poduct of thei masses and invesely as the squae of
More informationFrom last times. MTE1 results. Quiz 1. GAUSS LAW for any closed surface. What is the Electric Flux? How to calculate Electric Flux?
om last times MTE1 esults Mean 75% = 90/120 Electic chages and foce Electic ield and was to calculate it Motion of chages in E-field Gauss Law Toda: Moe on Gauss law and conductos in electostatic equilibium
More informationChapter 25. Electric Potential
Chapte 25 Electic Potential C H P T E R O U T L I N E 251 Potential Diffeence and Electic Potential 252 Potential Diffeences in a Unifom Electic Field 253 Electic Potential and Potential Enegy Due to Point
More information21 MAGNETIC FORCES AND MAGNETIC FIELDS
CHAPTER 1 MAGNETIC ORCES AND MAGNETIC IELDS ANSWERS TO OCUS ON CONCEPTS QUESTIONS 1. (d) Right-Hand Rule No. 1 gives the diection of the magnetic foce as x fo both dawings A and. In dawing C, the velocity
More informationCharge is that property of material due to which it shows electric and magnetic phenomena.
Electostatics Electostatics deals with the study of foces, fields and potentials aise fom static chages. In othe wods it is study of chages at est. Chage Chage is that cetain something possessed by mateial
More informationReview of Potential Energy. The Electric Potential. Plotting Fields and Potentials. Electric Potential of a Point Charge
eview of Potential negy Potential enegy U() can be used to descibe a consevative foce. efeence point (U) can be chosen fo convenience. Wok done by F : W F d s F d (1D) Change in P.. : U U f U i W Foce
More information1.1 THE ELECTRIC CHARGE
1.1 THE ELECTRIC CHARGE - In a dy day, one obseves "light spaks" when a wool pull is taken out o when the finges touch a metallic object. Aound the yea 1600, one classified these effects as electic phenomena.
More informationPrepared by: M. S. KumarSwamy, TGT(Maths) Page - 1 -
Pepaed by: M. S. KumaSwamy, TGT(Maths) Page - - ELECTROSTATICS MARKS WEIGHTAGE 8 maks QUICK REVISION (Impotant Concepts & Fomulas) Chage Quantization: Chage is always in the fom of an integal multiple
More informationPearson Physics Level 30 Unit VI Forces and Fields: Unit VI Review Solutions
Peason Physics Level 30 Unit VI Foces and Fields: Unit VI Review Solutions Student Book pages 66 631 Vocabulay 1. ampee: the flow of 1 of chage past a point in a conducto in 1 s chage migation: movement
More informationElectrostatics. 1. Show does the force between two point charges change if the dielectric constant of the medium in which they are kept increase?
Electostatics 1. Show does the foce between two point chages change if the dielectic constant of the medium in which they ae kept incease? 2. A chaged od P attacts od R whee as P epels anothe chaged od
More informationHopefully Helpful Hints for Gauss s Law
Hopefully Helpful Hints fo Gauss s Law As befoe, thee ae things you need to know about Gauss s Law. In no paticula ode, they ae: a.) In the context of Gauss s Law, at a diffeential level, the electic flux
More information2 E. on each of these two surfaces. r r r r. Q E E ε. 2 2 Qencl encl right left 0
Ch : 4, 9,, 9,,, 4, 9,, 4, 8 4 (a) Fom the diagam in the textbook, we see that the flux outwad though the hemispheical suface is the same as the flux inwad though the cicula suface base of the hemisphee
More informationPhysics Electrostatics: Coulomb s Law
A C U L T Y O E D U C A T I O N Depatment of Cuiculum and Pedagogy Physics Electostatics: Coulomb s Law Science and Mathematics Education Reseach Goup Suppoted by UBC Teaching and Leaning Enhancement und
More informationAppendix B The Relativistic Transformation of Forces
Appendix B The Relativistic Tansfomation of oces B. The ou-foce We intoduced the idea of foces in Chapte 3 whee we saw that the change in the fou-momentum pe unit time is given by the expession d d w x
More informationELECTRIC CHARGE AND ELECTRIC FIELD
Electic Chage and Electic Field MODULE - 5 Electicity and 5 ELECTRIC CHARGE AND ELECTRIC FIELD So fa you have leant about mechanical, themal and optical systems and vaious phenomena exhibited by them.
More informationELECTRIC CHARGES AND FORCES
ELECTRIC CHARGES AND ORCES 5 Conceptual Questions 5.1. An insulato can be chaged. Plastic is an insulato. A plastic od can be chaged by ubbing it with wool. 5.. A conducto can be chaged. A conducto can
More informationMAGNETIC FIELD INTRODUCTION
MAGNETIC FIELD INTRODUCTION It was found when a magnet suspended fom its cente, it tends to line itself up in a noth-south diection (the compass needle). The noth end is called the Noth Pole (N-pole),
More informationToday s Plan. Electric Dipoles. More on Gauss Law. Comment on PDF copies of Lectures. Final iclicker roll-call
Today s Plan lectic Dipoles Moe on Gauss Law Comment on PDF copies of Lectues Final iclicke oll-call lectic Dipoles A positive (q) and negative chage (-q) sepaated by a small distance d. lectic dipole
More information4. Compare the electric force holding the electron in orbit ( r = 0.53
Electostatics WS Electic Foce an Fiel. Calculate the magnitue of the foce between two 3.60-µ C point chages 9.3 cm apat.. How many electons make up a chage of 30.0 µ C? 3. Two chage ust paticles exet a
More informationVoltage ( = Electric Potential )
V-1 of 10 Voltage ( = lectic Potential ) An electic chage altes the space aound it. Thoughout the space aound evey chage is a vecto thing called the electic field. Also filling the space aound evey chage
More informationPhysics 11 Chapter 4: Forces and Newton s Laws of Motion. Problem Solving
Physics 11 Chapte 4: Foces and Newton s Laws of Motion Thee is nothing eithe good o bad, but thinking makes it so. William Shakespeae It s not what happens to you that detemines how fa you will go in life;
More informationJURONG JUNIOR COLLEGE Physics Department Tutorial: Electric Fields (solutions)
JJ 5 H Physics (646) Electic Fields_tutsoln JURONG JUNIOR COLLEGE Physics Depatment Tutoial: Electic Fields (solutions) No Solution LO Electic field stength at a point in an electic field is defined as
More informationReview: Electrostatics and Magnetostatics
Review: Electostatics and Magnetostatics In the static egime, electomagnetic quantities do not vay as a function of time. We have two main cases: ELECTROSTATICS The electic chages do not change postion
More informationPHYS 1444 Section 501 Lecture #7
PHYS 1444 Section 51 Lectue #7 Wednesday, Feb. 8, 26 Equi-potential Lines and Sufaces Electic Potential Due to Electic Dipole E detemined fom V Electostatic Potential Enegy of a System of Chages Capacitos
More informationPhysics 235 Chapter 5. Chapter 5 Gravitation
Chapte 5 Gavitation In this Chapte we will eview the popeties of the gavitational foce. The gavitational foce has been discussed in geat detail in you intoductoy physics couses, and we will pimaily focus
More informationChapter 22 The Electric Field II: Continuous Charge Distributions
Chapte The lectic Field II: Continuous Chage Distibutions A ing of adius a has a chage distibution on it that vaies as l(q) l sin q, as shown in Figue -9. (a) What is the diection of the electic field
More informationTAMPINES JUNIOR COLLEGE 2009 JC1 H2 PHYSICS GRAVITATIONAL FIELD
TAMPINES JUNIOR COLLEGE 009 JC1 H PHYSICS GRAVITATIONAL FIELD OBJECTIVES Candidates should be able to: (a) show an undestanding of the concept of a gavitational field as an example of field of foce and
More informationElectric Potential Potential Differences in a Uniform Electric Field Electric Potential and Potential Energy Due to Point Charges
P U Z Z L E R Jennife is holding on to an electically chaged sphee that eaches an electic potential of about 100 000 V. The device that geneates this high electic potential is called a Van de Gaaff geneato.
More informationUniversity Physics (PHY 2326)
Chapte Univesity Physics (PHY 6) Lectue lectostatics lectic field (cont.) Conductos in electostatic euilibium The oscilloscope lectic flux and Gauss s law /6/5 Discuss a techniue intoduced by Kal F. Gauss
More informationOSCILLATIONS AND GRAVITATION
1. SIMPLE HARMONIC MOTION Simple hamonic motion is any motion that is equivalent to a single component of unifom cicula motion. In this situation the velocity is always geatest in the middle of the motion,
More informationPHYSICS 272H Electric & Magnetic Interactions
PHYSICS 7H Electic & Magnetic Inteactions Physics couse home page: http://www.physics.pudue.edu/academic-pogams/couses/all_couses.php Blackboad Lean: https://mycouses.pudue.edu/webapps/login/ Couse Content
More informationworking pages for Paul Richards class notes; do not copy or circulate without permission from PGR 2004/11/3 10:50
woking pages fo Paul Richads class notes; do not copy o ciculate without pemission fom PGR 2004/11/3 10:50 CHAPTER7 Solid angle, 3D integals, Gauss s Theoem, and a Delta Function We define the solid angle,
More informationChapter 5. Applying Newton s Laws. Newton s Laws. r r. 1 st Law: An object at rest or traveling in uniform. 2 nd Law:
Chapte 5 Applying Newton s Laws Newton s Laws st Law: An object at est o taveling in unifom motion will emain at est o taveling in unifom motion unless and until an extenal foce is applied net ma nd Law:
More informationForce between two parallel current wires and Newton s. third law
Foce between two paallel cuent wies and Newton s thid law Yannan Yang (Shanghai Jinjuan Infomation Science and Technology Co., Ltd.) Abstact: In this pape, the essence of the inteaction between two paallel
More informationReview for Midterm-1
Review fo Midtem-1 Midtem-1! Wednesday Sept. 24th at 6pm Section 1 (the 4:10pm class) exam in BCC N130 (Business College) Section 2 (the 6:00pm class) exam in NR 158 (Natual Resouces) Allowed one sheet
More information