Given the seconds \$t\$ it takes a capacitor (with farads \$C\$) to discharge from 5 volts (\$V_0\$) to 0 volts (\$V_t\$), how do you calculate the effective ohms of resistance R in a circuit?
Based on the standard capacitor voltage discharge formula \$V_t = V_0(1-e^{-t/RC})\$, would the resistance formula be \$R = \dfrac{-t}{C \cdot log(1-V_t/V_0)}\$?