And the WALL-WART is plugged into the arduino external dc barrel jack ?
Regarding the circuit. You said the no load resistance is 1 megaohm and the 1 lb resistance is 60k.
If you connect it the way it is shown in the fritzing (using a one megaohm resistor) then the value is
NO LOAD
torque = 5V * 1 megaohm/(1 megaohm+1 megaohm)= 5* (1/2)= 2.5V (2.5/0.0048=520 ANALOG COUNTS
LOAD =1 POUND
torque = 5V 1 megaohm(1 megaohm + 60k)=5V (1000000/1060000)=> 5V * (0.943396)=4.7169811 V
4.7169811 V/0.00488=966 ANALOG COUNTS
/* Map an analog value */
void setup() {}
void loop()
{
int sensor = analogRead(0);
sensor = map(sensor, 1023, 0, 966, 520);
// 0 lbs = 966
// 1 lb = 520
// 966-520=446 counts
// Force in lbs = (966-sensor)/446
// Test: Let sensor = 966=> torque = (966-966)/446= 0 lbs force
// Let sensor = 520=> torque = (966-520)/446=446/446 = 1.000000
NOTE: THIS CALCULATION MUST BE DONE USING float variable type to get fractions of a lb. (torque should be type float)
torque = (966-sensor)/446=446/446 = 1.000000
Serial.print( torque); // print sensor value
}