Properties Of Solids And Liquids Question 550
Question: If two rods of length L and 2L having coefficients of linear expansion $ \alpha $ and $ 2\alpha $ respectively are connected so that total length becomes 3L, the average coefficient of linear expansion of the composite rod equals :
Options:
A) $ \frac{3}{2}\alpha $
B) $ \frac{5}{2}\alpha $
C) $ \frac{5}{3}\alpha $
D) none of these
Show Answer
Answer:
Correct Answer: C
Solution:
$ (3L){\alpha _{ _{eff}}}\Delta \theta =L\alpha \Delta \theta +2L(2\alpha )(\Delta \theta ) $
$ \therefore $ $ {\alpha _{eff}}=\frac{5}{3}\alpha $
