Question

Exam 1 (Chapter 21, 22 and 23 1. The Coulomb's force between a proton and an electron is 2.27X10"times greater than the gravitational force. If the two forces were equal, what should the size of the elementary charge be A) 1.60 x 10°C D) 2.27 x 10°C 8) 3.36 x 10°C E) 4.41 x 10°C 123 x 10°C 2. An electric field with a magnitude of 6.0 x 10' N/C is directed parallel to the positive y axis. A particle with a charge q = 4.8 x 10-™C is moving along the x axis with a speed v 3.0 x 10 m/s. The force on the charge is approximately A) 8.6 x 10-N perpendicular to the xy plane. B) 2.9 x 10-N in the y direction. C) 8.6 x 10-N in the x direction. D) zero. E) 2.9 x 10-N in the x direction. A rod of infinite length has a charge per unit length of 2 (g/l). Gauss's law makes it easy to determine that the electric field strength at a perpendicular distance r from the rod is, in terms of k = (411E0)-2, A) kW/PB) kr C) 4tk/ D) 2K/ E) zero

Answer 1

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