Two rods of different materials are placed between massive walls as shown in figure. The cross section of the rods is A, their moduil of elastricity are `E_(1)` and `E_(2)` respectively. If rods are heated by t degrees, then (coefficients of liner expansion of material of rods are `alpha_(1)` and `alpha_(2)` respectively)
A. the strain produced in both rods is equal
B. the stress produced in both the rods is equal
C. the force exerted by one rod on the other is `(alpha_(1)l_(1)+alpha_(2)l_(2))/((l_(1))/(E_(1))+(l_(2))/(E_(2)))At`
D. the force exerted by one rod on the other is `((E_(1)-E_(2))^(2)A)/(E_(1)+E_(2))`