J

Jog: A button on the control panel that moves the crosshead up or down manually. Used to manually position the crosshead prior to testing as a quick method to grip or position a test specimen.

L

Linear Density: Linear density is a measure of mass per unit length.

Load Cell: A transducer which converts a value of force into an electrical signal.

LOP: Limit of Proportionality is the force at the point on a stress/strain curve where the strain is no longer proportional to the stress.