Example 12.5: To measure a base line, a steel tape 30 m long, standardised at 15° C with a pull of 80 N was used. Find the correction per tape length, if the temperature at the time of measurement is 25° C and the pull exerted is 150 N. Take Young's modulus E = 2 x 10^5 N/mm2 and coefficient of thermal expansion a = 11.2 × 10^6/°C. Cross-sectional area of tape is 8 mm2.