Passage - II: A copper rod of length I_1 and a steel rod of length I_(2), both having the same area of cross-section, are placed end to end between two rigid supports X and Y such that their system just fits between the supports with no initial stress in the rods. Temperature of the rods is now increased by Delta T. If Y_( Cu) is the Young's modulus of copper and alpha_(Cu) its coefficient of linear expansion, while Y_(St) is the Young's modulus of steel and alpha_(St) its coefficient of linear expansion, answer the following questions. (Assume that area of cross-section does not change and the rods do not bend. Also assume that there is no deformation of the supports.) As the temperature is increased by Delta t, length of the copper rod will be

Passage - II: A copper rod of length I_1 and a steel rod of length I_

1.	Passage - II: A copper rod of length I_1 and a steel rod of length I_(2), both having the same area of cross-section, are placed end to end between two rigid supports X and Y such that their system just fits between the supports with no initial stress in the rods. Temperature of the rods is now increased by Delta T. If Y_( Cu) is the Young's modulus of copper and alpha_(Cu) its coefficient of linear expansion, while Y_(St) is the Young's modulus of steel and alpha_(St) its coefficient of linear expansion, answer the following questions. (Assume that area of cross-section does not change and the rods do not bend. Also assume that there is no deformation of the supports.) As the temperature is increased by Delta t, length of the copper rod will be
Answer» `I_(2)` `I_(1) ( 1+ alpha_(Cu) Delta t) ` `I_(1) ( 1+ alpha_( Cu) Delta t- (F)/( AY_(Cu) ) )` `I_(1)[ 1+ (alpha_(Cu) - alpha_(ST) ) Delta t]` Answer :B