Honors Physics Electric Potential Energy and Potential Difference Worksheet 1. Potential of Two Point Charges Problem Two point charges q1 = -88.0 nC & q2 = 360 nC are located at the fixed positions at x1= 22.0 cm and x2 = 96.0 cm on the x-axis. (A) What is the electric potential due to both charges at x = 50.0 cm? (B) Where on the x-axis is the electric potential due to both charges equal to zero? (C) How much work is required to move a third charge q3 =13.0 mC from the origin to x = 50.0 cm along any path (that does not go through one of the charges)? (D) If a fourth charge q4 with a charge of -11.0 mC and a mass of 3.90 gm is released from rest at the origin, what is the charge's final speed and direction when it is very far away from the other two charges? 2. A proton is accelerated from rest through a potential of 500 volts. What is its final kinetic energy? 3. What is the final velocity of the proton in the previous problem? (The mass of the proton is 1.67 x 10-27 kg.) Ai. 4. If Q1 and Q2 are equal and oppositely charged, what is the potentialat point B? :2 £1, . 5. If Q1 is twice Q2 and both are positive, where can a point of zero potential be found? @at 6. An electric field is created by a Van de Graaf generator. A test charge of (q) is placed in the field at a distance r. a) If the test charge has a magnitude of +1q write an expression for i) the potential energy between the charges ii) the potential of the system b) if the test charge has a magnitude of +2q write an expression for i) the potential energy between the charges ii) the potential of the system 7. The potential differer1te between a storm cloud and the ground is 100-million volts. If a charge of 2.0 C transfers (via a lightning bolt), how much potential energy was transferred? 8. A system involves a +6j..JCcharge and a +4j..JCcharge initially separated by an infinite distance.' a) How much work is required to bring them 150 cm from each other? b) What is the total voltage at a point in the middle of the system? 9) For the uniform field shown on the right, an electron is released from rest from plate B. Determine the: a) work done by the field b) force on the charge -t c) acceleration of the charge -t d) the speed of the charge when it reaches plate A I E = 500 N/C -t e) change in potential energy -t B A 10. A chargeof -4.0j..JCis initially400 mmfroma fixed chargeor -6.0j..JC and is then movedto a position90 cm fromthe fixed charge. a) what is the change in the mutual potential energy of the charges? b) Does this change depend on the path through which the one charge is moved? *11. A proton moving directly toward another fixed proton has a speed of 5.0 m/s when the two are 100 cm apart. 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