Q20 of 29 Page 69

A steel rod (Y= 2.0 × 1011 Nm-2; and α = 10-5 C-1) of length 1 m and area of cross-section 1 cm2 is heated from 0° C to 200° C, without being allowed to extend or bend. What is the tension produced in the rod?

Original Question has and α = 10-5


Since heat is travelling in single direction, therefore it is a case of 1D Thermal Expansion or linear expansion.


We know for thermal expansion, change in length is given by



Re-arranging it will give,




Now, for calculating tension we will use a relation between young modulus and Force,






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