Hardness is determined by the amount of indentation on the material. Smaller the indentation, harder is the stuff and vice versa.
A Strain Gauge is a form of the transducer which can convert applied force, pressure, tension into a change in electrical resistance which can be displayed on the screen.
A strain rosette is a combination of three independent strain gauges which are connected in perpendicular axes direction. These gauges are attaches in any three directions to measure the shear strain.
A load cell is such a transducer that can convert the applied force into an electrical signal, and its magnitude is directly proportional to the other one. Hydraulic, Pneumatic, piezoelectric and strain gauge are the various types of the load cell in which the most important is a strain gauge.
Spring is a light metal spiral set up which is connected with some weight at one end, and its other end is attached to a wall. This material shows elastic property, and its length varies
The Modulus of Rigidity of a material is the relation between shear stress and shear strain of a particular substance and defined as the ratio of shear stress to displacement
Fatigue is defined as the condition of a material where it cracks or fails because of the repeated cyclic stresses which are applied below the ultimate strength.
The impact is defined as the impedance of material to rapidly applied loads. An Impact test is a dynamic test in which a selected specimen which is usually notched in struck and broken by a single bow in a specially designed machine
Shear stress is defined as the shear force which acts on a particular area and it is responsible for causing a deformation of material through motion along the plane or a no. of planes operating parallel to the applied stress
Hardness is a fundamental property of a material which defines its resistance to indentation which is determined by measuring its permanent depth of indentation.