Question:
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason $R$.
Assertion $A$ : When a rod lying freely is heated, no thermal stress is developed in it. Reason $\mathrm{R}$ : On heating, the length of the rod increases. In the light of the above statements, choose the corect answer from the options given below :
Correct Option: , 3
Solution:
(3)
When a rod is free and it is heated then there is no thermal stress produced in it. The
rod will expand due to increase in temperature. so both a $\backslash \& \mathrm{R}$ are true.