# Given below are two statement : one is labelled as Assertion A

Question:

Given below are two statement : 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 $R$ : On heating the length of the rod increases.

In the light of the above statements, choose the correct answer from the options given below:

1. Both $A$ and $R$ are true but $R$ is NOT the correct explanation of $\mathrm{A}$

2. $A$ is false but $R$ is true

3. $A$ is true but $R$ is false

4. Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is the correct explanation of $\mathrm{A}$

Correct Option: 1

Solution:

$A$ and $R$ are true but $R$ is not the correc explanation of $\mathrm{A}$.