The length of two metallic rods at temperatures `theta` are `L_(A)` and `L_(B)` and their linear coefficient of expansion are `alpha_(A)` and `alpha_(B)` respectively. If the difference in their lengths is to remian constant at any temperature thenA. `L_(A)//L_(B) = alpha_(A)//alpha_(B)`B. `L_(A)//L_(B) = alpha_(B)//alpha_(A)`C. `alpha_(A) = alpha_(B)`D. `alpha_(A) alpha_(B) = 1`

The length of two metallic rods at temperatures `theta` are `L_(A)` an

1.	The length of two metallic rods at temperatures `theta` are `L_(A)` and `L_(B)` and their linear coefficient of expansion are `alpha_(A)` and `alpha_(B)` respectively. If the difference in their lengths is to remian constant at any temperature thenA. `L_(A)//L_(B) = alpha_(A)//alpha_(B)`B. `L_(A)//L_(B) = alpha_(B)//alpha_(A)`C. `alpha_(A) = alpha_(B)`D. `alpha_(A) alpha_(B) = 1`
Answer» Correct Answer - B Change in `L_(A)` = change in `L_(B)` i.e., `Delta L_(A) = L_(B)` `rArr alpha_(A)Delta T L_(A)=alpha_(B)Delta T L_(B)` or, `alpha_(A)L_(A)=alpha_(B)L_(B)`.

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