Ian the iron worker is tightening a bolt. If Ian weighs 180 pounds and needs to tighten the bolt with all of his weight to 120 foot pounds of torque, how many inches along the handle from the center of the bolt should he grip his wrench

2/3 feet (=0.667 feet) from center of rotation

Step-by-step explanation:

Torque = distance from center of rotation x perpendicular force

in our case, perpendicular force is given as 180 lbs (assuming that the wrench is horizontal to the ground and the only force on the wrench is all the workers's weight)

torque is given to be 120 ft-lbs

using the formula above:

Torque = distance from center of rotation x perpendicular force

120 = distance from center of rotation x 180

distance from center of rotation = 120 / 180 = 2/3 (=0.667)