Two rods A and B of equal free lengths hang vertically from ceiling  60 cm apart and at bottom attached to a light horizontal bar. The bar remain in horizontal position when carry a load of 5000 kg at a distance 20 cm from rod A. If the stress in rod B is 50 N/mm², find the stress in A (in N/mm²) up to two decimal places. Take Young's moduli are ${\mathrm{Y}}_{\mathrm{B}}=9\times {10}^{10} \mathrm{N}/{\mathrm{m}}^2,{\mathrm{Y}}_{\mathrm{A}}=2\times {10}^{11} \mathrm{N}/{\mathrm{m}}^2\text{ and }\mathrm{g}=10 \mathrm{m}/{\mathrm{s}}^2$.

• A

  $333.33 \mathrm{N}/{\mathrm{mm}}^2$

• B

  $222.22 \mathrm{N}/{\mathrm{mm}}^2$

• C

  $111.11 \mathrm{N}/{\mathrm{mm}}^2$

• D

  $55.55 \mathrm{N}/{\mathrm{mm}}^2$