Resolução - Halliday - Volume 3 - Eletricidade E Magnetismo - P22 028

Transcript

28. If the relative difference between the proton and electron charges (in absolute value) were qp − |qe | = 0.0000010 e then the actual difference would be qp − |qe | = 1.6 × 10−25 C . Amplified by a factor of 29 × 3 × 1022 as indicated in the problem, this amounts to a deviation from perfect neutrality of

 ∆q = 29 × 3 × 1022 1.6 × 10−25 C = 0.14 C in a copper penny. Two such pennies, at r = 1.0 m, would therefore experience a very large force. Eq. 22-1 gives (∆q)2 F = k 2 = 1.7 × 108 N . r