A copper bar of $25 cm$ length is fixed by means of supports at its ends. Supports can yield (total) by 0.01 cm. If the

temperature of the bar is raised by $100° C$, then the stress induced in the bar for ${\alpha }_c$ $= 20 x {10}^{-6}/°C$ and 

• • 1

    $2 x {10}^{2 }kg/c{m}^2$

  • 2

    $4 x {10}^2 kg/c{m}^2$

  • 3

    $8 x {10}^2 kg/c{m}^2$

  • 4

    $16 x {10}^2 kg/c{m}^2$