C17 HW Hints
C17 PP11 - Neuron Capacitance, C=0.27pF
Q =C*deltaV, so if deltaV=(0.060)-(-.085)=0.145V, then
Q = 0.27E-12F * 0.145V = _____C
Now each ion carries 1.6E-19 C, so convert charge in C to #ions
Q11 - Recall connection between E and V. E is the 'slope' of the V field,
MC11 - Recall that E is always perpendicular to constant V lines and
E points 'downhill,' i.e., from higher to lower voltage.
P91 - r=0.15m, air breaks down (spark) when E=|E| exceeds 3MV/m
The voltage around and up to the surface of a spherically symmetric charge
distribution is the same as a point charge, V=kQ/r