Deflecting beam Torque wrench

A calibrated wrench which indicates the amount of torque being applied to a nut or bolt. This is done by measuring the amount the beam of the wrench deflects when the torque is being applied. According to Hooke's law of elasticity, the beam will deflect the same amount each time a given amount of torque is applied by the wrench. The indication of the amount of torque is read by the position of a pointer attached to the drive of the wrench, over a fixed scale fastened to the beam of the wrench.