Physics

Problem

The coefficient of linear expansion of steel and brass are

11 \times 10^{-6}/^{\circ}\text{C}

and

19 \times 10^{-6}/^{\circ}\text{C}

, respectively. If their difference in lengths at all temperatures has to be kept constant at 30 cm, their lengths at

0^{\circ}\text{C}

should be a. 71.25 cm and 41.25 cm b. 82 cm and 52 cm c. 92 cm and 62 cm d. 62.25 cm and 32.25 cm