Chapter 21 potential 第八章静电场 Chapter 21 Electric potential 1. Electric potential and potential difference 2. Relation between electric potential and Electric field 3. The calculation of electric potential 4. Equipotential Surfaces 5. Electrostatic Potential Energy
Chapter 21 potential 第八章静电场 1. Electric Potential and Potential Difference 2. Relation Between Electric Potential and Electric Field 3. The Calculation of Electric Potential 4. Equipotential Surfaces 5. Electrostatic Potential Energy
Chapter 21 potential 第八章静电场 New words and Expressions electric potential 电势 potential difference 电势差,电压 circulation theorem 环路定理 electric potential energy 电势能 equipotential surfaces 等势面 electric potential gradient 电势梯度
Chapter 21 potential 第八章静电场 New words and Expressions electric potential 电势 potential difference 电势差,电压 circulation theorem 环路定理 electric potential energy 电势能 equipotential surfaces 等势面 electric potential gradient 电势梯度
Chapter 21 potential 第八章静电场 21-1&21-8 Electric Potential and Potential Difference(p503-505, p515) To study the electric field from the w, we introduce v(electric potential). 1. Features of electrostatic force Coulomb's aw for 1 g,g F electrostatic force 2 Newton 's law for nmin gravitational force: F=G Mathematically identical! Many properties for the gravitational may also be true for electrostatic forces
Chapter 21 potential 第八章静电场 To study the electric field from the W, we introduce V (electric potential). 21-1&21-8 Electric Potential and Potential Difference (p503-505, p515) 1. Features of Electrostatic Force Coulomb’s Law for electrostatic force: 2 1 2 4 0 1 r q q F Newton’s Law for gravitational force: 2 1 2 r m m F G Mathematically identical! Many properties for the gravitational may also be true for electrostatic forces
Chapter 21 potential 第八章静电场 1)Work done by electrostatic Force 点电荷的电场 Electric field of a point charge dW=anE·da B ggo 4兀F,d7 B F·dl= rdl cos e=rdr q40 0 4π60
Chapter 21 potential 第八章静电场 q 1) Work done by Electrostatic Force 0 q r W q E l d d 0 r l r qq d 4π 3 0 0 r dl rdl cos rdr r r qq W d 4π d 2 0 0 点电荷的电场 Electric field of a point charge l d dr Ar A Br B E
Chapter 21 potential 第八章静电场 w= go r's dr B 4兀E0nr dr入O ggo B 4πE0 结果:W仅与q的始末 位置有关,与路径无关 0 任意电荷的电场(视为点电荷的组合) E=∑E,W=qE=∑ q,E2·dl
Chapter 21 potential 第八章静电场 B A r r r qq r W 2 0 0 d 4π 0 q r l d dr Ar A Br B E ) 1 1 ( 4π 0 0 A B r r qq 结果: 仅与 的始末 位置有关，与路径无关. 0 W q 任意电荷的电场（视为点电荷的组合） i E Ei l W q E l 0 d l i i q E l 0 d