76. (a) The charge qthat flows past any cross section of the beam in time ∆tis given by q = i∆t, and the number of electrons is N = q/e = (i/e)∆t. This is the number of electrons that are accelerated. Thus N=××=×−−(....050160 1031 1061911A)(0.10 10s)C(b) Over a long time tthe total charge is Q = nqt, where nis the number of pulses per unit time and qis the charge in one pulse. The average current is given by iavg= Q/t = nq. Now q = i∆t= (0.50 A) (0.10 ×10–6s) = 5.0 ×10–8C, so
This is the end of the preview. Sign up
access the rest of the document.