question_answer 32)

                  A rod of length I and negligible mass is suspended at its two ends by two wires of steel (wire A) and aluminium (wire B) of equal lengths. The cross-sectional areas of wires A and B are 1.0 mm2 and 2.0 mm respectively.                 \[({{Y}_{Al}}70\times {{10}^{9}}N{{m}^{-2}}\,\,\text{and }\,{{Y}_{steel}}=\text{ }200\times {{10}^{9}}N{{m}^{2}})\]                 (a) Mass m should be suspended close to wire A to have equal stresses in both the wires.                 (b) Mass m should be suspended close to B to have equal stresses in both the wires.                 (c) Mass m should be suspended at the middle of the wires to have equal stresses in both the wires.                 (d) Mass m should be suspended close to wire A to have equal strain in bolt wires.                

Answer:

                  (b, d) Refer Model Numberial 20 of Chapter 9, New Millennium Physics, Class XI.