Objective The objective of the experiment was to test the st

Objective: The objective of the experiment was to test the strain gauge to find the stress and strain of the aluminum with selected applied forces. Theory: Stress and strain are two concepts that are commonly discussed in engineering. They are important topics because mostly everything will be subjected to outside forces. Strain is the response of a system to an applied stress. When a force is applied to a material, it causes a malformation in the material. Strain is equal to the amount of deformation in the direction of the applied force divided by the initial length of the material. Stress is defined as the force divided by the unit area. (I)Young\'s Modulus is equal to the stress divided by the strain. Young\'s Modulus is used to describe the elasticity of a material or the tendency of a material to bend.^(2) If someone wants to test the strain on the outside of a space shuttle, they are not going to want| to cause permanent damage. They only want to cause elastic deformation or bending, so the material will go right back to the way it was before the strain. Once a material bends to the extent where it is irreversible, it is said to have plastic deformation. There are many different tools used to test stress and strain, one of them happens to be a strain gauge. A strain gauge is a device that measures the strain of a material at a given point of attachment.^(3) A strain gauge is a sensor whose resistance changes when the force is applied. The strain that\'s placed on the material by the external influence is measured by the change in the electrical resistance. The more strain the material experiences, the more resistance the strain gauge exhibits.(4) Strain gauges are placed on a material simply to see how much strain it is experiencing. Electrical resistance strain gauges are commonly used for more precise measurements of strain. They are small, rectangular foils with maze-like wiring patterns that connect to electrical cables. The foil is attached to the material the strain needs to be measured for with adhesive. The electrical cables are soldered onto the material, and then the wires are connected to a circuit monitor. Once the strain gauge is mounted on the material, it is ready to test for strain. When the material is strained, the foil is bent and the wires become deformed. The resistance of the wires increases as the width of the metal changes, because it is harder for the electrons to flow through. When the monitor measures the change in the resistance, the monitor is also measuring the strain.(5) I need paraphrasing and use different words

Solution

objective: To find stress and strains for given material alluminium by applying different forces by using strain gauges.

Theory: Stress and strain are commonly used in engineering.

We plot the stress-strain curve by using universal testing machine by applying different loads.It is difficult to calculate stress because

   stress=(applied load/Area of rod at that instant)

  But it is diffficult to measure the area So we take the values of the elongation.That is the reason we take on X axis we take strain and 0n Y axis We take stress.

   Stress=Strain*Youngs modulus

Youngs modulus is different for different materials.It depends up elongation.

If some one want to measure the strain in space that is difficult to measure.They just want to elonate that material and it may again come back to the same pont is called ELASTICITY.If the material bends then it is not coming back to original position for applied load then it is called as PLASTICITY.They are different testing machines to calcukate the stress and strain but strain gauge is one among the machines.

The strain gauge is sensor type it is attached to the measuring specimen.This is an elecrical device used to measure with help of resistence in the circuit.More resistence experiences more strain.This strain gauge is highly accurate and gives the value of strain in micron level.These are small rectangular foils connected to electrical wires.The foils is attached to the material the strain needs to be measure.The electrical wires are soldered onto the material and these are coonected to monitor.When the material is strained,the foil bends and the wire deformed.The resistence increases width of the metal increase and electrons flow will get stopped.Moniter measyres the chnges in the resistence and displays on the screen.