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Electric Potential Difference Created by Point Charges. 19.3. Derivation. Potential of a Point Charge. V is NOT the absolute potential V IS the potential difference if a test charge were moved to a distance of r from infinity. Example.
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Potential of a Point Charge • V is NOT the absolute potential • V IS the potential difference if a test charge were moved to a distance of r from infinity
Example • Find the amount that a point charge of -2 C affects the potential at a distance of 3 m away. • V = -5990 V
Two or more charges • Find the potentials due to each charge at that location • Add the potentials together to get the total potential
Example • Two charges are 1 m apart. The charges are +2 C and -4 C. What is the potential 1/3 and 2/3 of the way between them? • 0 V and -80910 V
Example - EPE • How much work is done (EPEf – EPE0) to bring two electrons to a distance of 5.3x10-11 m to the nucleus of a Helium atom (q = 3.2x10-19C)? • W = 1.52x10-17 J
Practice Work • Try these potentially challenging problems! • 571 CQ 2, 3, 6, 7, 9, P 11-16 • Total of 11 Problems