Question 1 Report
Which of the following statement is not correct about loaded spiral spring?
The statement that is not correct about a loaded spiral spring is: "Up to the yield limit, extension is no longer proportional to the applied load." The yield limit is the point at which the material of the spring starts to deform plastically, which means that it undergoes permanent deformation even after the load is removed. Beyond the yield limit, the spring will no longer return to its original shape or form. Before the yield limit is reached, the extension of the spring is proportional to the load applied, as stated in the first option. This means that if you double the load applied to the spring, the extension will also double, as long as the elastic limit is not exceeded. Similarly, when the load is removed, the contraction of the spring is proportional to the load removed, as stated in the second option. However, once the yield limit is exceeded, the extension of the spring is no longer proportional to the applied load, as stated in the third and fourth options. This is because the spring has undergone permanent deformation, and will not return to its original shape or form. The amount of extension will depend on the load applied and the amount of plastic deformation that has occurred. The last option is a general statement about elasticity, and is not specific to loaded spiral springs. If a material regains its shape or form after deformation, it is said to be elastic. Therefore, the correct answer is option (C): "Up to the yield limit, extension is no longer proportional to the applied load."