In the right figure, the top panel of graph shows the potential V as a function
ID: 3162846 • Letter: I
Question
In the right figure, the top panel of graph shows the potential V as a function of position x in three regions I, II, and III. Accordingly, four parallel plates, A through D, can be setup to realized the distribution of potential, as schematically drawn in the bottom panel of the figure. The unit of the distance is cm, and the unit of potential is V. The potential on plate D is 5 V You are correct. Computer's answer now shown above Previous Tries Your receipt no s 158-6481 The magnitude e. absolute value) of the electric field in region II is 0 V/m You are correct. Computer's answer now shown above Previous Tries Your receipt no s 158-3368 A particle carries -4e charge (i.e. q 6.4x10 19 C) and is free to move in region III. Its initial velocity is zero at position x 8 cm. When it leaves region III, how much is the kinetic energy of this particle in ev (electron-volt)? eV Submit Answer Tries 0/2 V(V) 10 10 II 2 4 6 8 x(cm) x(cm)Explanation / Answer
q1 = -4e = -6.4 * 10^-19 C
vi = 0 , x1 = 8 cm = 0.08 m
x2 = 0.04 m
Slope = dy/dx = (0-10)/(4-8) V/cm = 2.5 * 10^2 V/m
F = -q * dV/dx = q * Slope of V(x) vs x = -6.4 * 10^-19 * 2.5 * 10^2 N = -1.6 * 10^-16 N
KE = Fd = -1.6 * 10^-16 N * (-0.04 m) = 6.4 * 10^-17 J