31.The temperature of a wire of length 1 metre and area of cross-section is

31.The temperature of a wire of length 1 metre and area of cross-section is 1 cm²  is increased from 0°C to 100°C. If the rod is not allowed to increase in length, the force required will be  (α=10^-5/°C and Y=10¹¹ N/m²)

(a)   10³ N                                           (b) 10⁴ N

(c) 10⁵ N                                             (d) 10⁹ N

ANSWER-B

(6)