Loaded voltage divider

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This is a model of a simple resistive voltage divider (attenuator), including the effect of load resistance. The model can also be used to determine the effect of load resistance on the linearity of a continuously variable slide-wire potentiometer (e.g. Helipot) by specifying the total resistance Rt and the fraction counter-clockwise rotation alpha, rather than R1 and R2 

Variable Sheet
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St Input     Name    Output    Unit      Comment
   9         Ein               volts     Input voltage (volts, mv, µv)
   5000      R1                Ohms      Resistor 1 (Ohms,KOhms,MOhms)
   10000     R2                Ohms      Resistor 2 (Ohms,KOhms,MOhms)
   100000    RL                Ohms      Load resistance (Ohms,KOhms,MOhms)
             Eout    5.8064516 volts     Output voltage (volts, mv, µv)
             IL      .05806452 mA        Current through RL (Amps, mA, µA)
             E1      3.1935484 volt      Voltage across R1 (volts, mv, µv)
             I1      .63870968 mA        Current through R1 (Amps, mA, µA)
             I2      .58064516 mA        Current through R2 (Amps, mA, µA)
             R2eff   9090.9091 Ohms      R2 & RL in parallel (Ohms,KOhms,MOhms)
             P1      2.0397503 mW        Power dissipated in R1 (watts, mW)
             P2      3.371488  mW        Power dissipated in R2 (watts, mW)
             PL      .3371488  mW        Power dissipated in RL (watts, mW)
             Rt      15000     Ohms      Total end-to-end resistance of pot
             alpha   .66666666           Fractional rotation of pot (unitless)

Rule Sheet
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S Rule
* R2eff=1/(1/RL+1/R2)        "Rule for parallel resistors
* E1+Eout=Ein                "Kirchoff's Law for voltage
* I1=I2+IL                   "Kirchoff's Law for current
* E1=I1*R1                   "Ohm's Law for R1
* Eout=I2*R2                 "Ohm's Law for R2
* Eout=IL*RL                 "Ohm's Law for RL
* Eout=Ein*R2eff/(R2eff+R1)  "Voltage divider equation
* Eout=I1*R2eff              "Ohm's Law for R2eff
* P1=I1*E1                   "Joules Law for R1
* P2=I2*Eout                 "Joules Law for R2
* PL=IL*Eout                 "Joules Law for RL
* Rt=R1+R2                   "Total end-to-end resistance of pot
* alpha=R2/Rt                "Fractional rotation of pot