An uncharged conductor is charged positively by a nearby charged rod, causing the right end of the conductor to become positively charged as well. An electron in an electric field of 6 x 10^19 N/C experiences an acceleration of 1.05 x 10^17 m/s^2. The electrical potential is 4.2 x 10^5 V at a distance of 1.71 m from a point charge of 8.0 microC. A 0.25 microFarad capacitor connected to a 400 V battery will charge to 1 x 10^-4 C. The resistance of a copper wire increases by 39% when its temperature rises from 20°C to 120°C.

1. An uncharged conductor is supported by an insulating stand. I pass a positively charged rod near
the left end of the conductor, but do not touch it. The right end of the conductor will be: 8. A.
negative B. positive C. neutral D. attracted In x-ray machines, electrons are subjected to electric
fields as great as 6 x 10 N/C. Find an electron's acceleration in this field. (m, = 9.1x 1031 kg,
qd-=-1.6x10", C; F--ma) 9. A. 1.05 x 10'"m/s B. 5.37 x 10' m/s C. 4.63 x 10°m/s D. 3.64 x
10 m/s' 10. At what distance from a point charge of 8.0 microCoul would the electrical potential
be 4.2 x 10* V? (k 9x 10° N-m'/c) A. 0.58 m B. 0.76 m D. 2.94 m A 0.25 microFarad
capacitor is connected to a 400 V battery. Find the charge on the capacitor. 11. A. 1.2 x101" c B.
1.0x10"C C. 0.040 C D. 0.020 C 12. By what factor is the resistance of a copper wire changed
when its temperature is increased from 20'C to 120°C? (the temperature coeficient of
resistivity for copper 3.9 x 10*% A. 0.72 B. 1.06 C. 1.39 D. 1.44
Solution
(1) B: Positive
(2) Eq=ma ==> a=1.05x10 17
m/s 2
(3) v=kQ/r ==> r=1.71 m
(4) C=Q/V ==> Q=1 x 10 -4