The Young’s modulus of a material describes how it behaves under a load. It is defined as the ratio of stress to strain. Stress is force per unit area, or pressure, measured in Pa, and strain is a ratio of lengths, so has no units. Therefore, Young’s modulus is a measure of pressure and has SI units of Pa.Comprises a scale plate carrying a 0 to 30mm scale, and a vernier scale readable to 0.1mm. Both have bars with clamping screws for the wires and hooks for the tension weight and loading masses. A ceiling clamp is provided for the upper ends of the wires, together with a pair of large wood screws for attaching it to a convenient overhead beam, door frame etc.A tension weight, mass 1.3kg approx., for the comparison wire is also included.Supplied WITHOUT load masses or wires.In addition to the apparatus, the following items are required:Set of wires (a mixed set is available to purchase separately)Screw Gauge Micrometer (B8R06348)Slotted 100g masses (B8A73088)Safety Goggles