The pressure that has to be applied to the ends of a steel wire

The pressure that has to be applied to the ends of a steel wire of length 10 cm to keep its length constant when its temperature is raised by 100°C is: (For steel, Young’s modulus is 2×1011 N m–2 and coefficient of thermal expansion is 1.1×10-5 K-1)

  1. 2.2 × 106 Pa
  2. 2.2 × 107 Pa
  3. 2.2 × 108 Pa
  4. 2.2 × 109 Pa

Answer

L x Cofficient of thermal expansion = P/Y

After putting all the values, you get

P = 2.2 × 108 Pa

The correct option is C.