P27_001.PDF

(53 KB) Pobierz

Chapter 27 - 27.1

1. (a) The charge that passes through any cross section is the product of the current and time. Since

4 . 0min=(4 . 0min)(60s / min) = 240s, q = it =(5 . 0A)(240s) = 1200C.

(b) The number of electrons N is given by q = Ne ,where e is the magnitude of the charge on an

electron. Thus N = q/e = (1200C) / (1 . 60

10 − 19 C)=7 . 5

10 21 .