NEET Solved Paper 2016 Question 16
Question: Coefficient of linear expansion of brass and steel rods are $ {\alpha_1} $ and $ {\alpha_2}. $ Lengths of brass and steel rods are $ {\ell_1} $ and $ {\ell _{.2}} $ respectively. If $ ({\ell_2}-{\ell_1}) $ is maintained same at all temperatures, which one of the following relations holds good?
Options:
A) $ {\alpha_1}{\ell_2}={\alpha_2}{\ell_1} $
B) $ {\alpha_1}\ell _2^{2}={\alpha_2}\ell _1^{2} $
C) $ \alpha _1^{2}{\ell_2}=\alpha _2^{2}{\ell_1} $
D) $ {\alpha_1}{\ell_1}={\alpha_2}{\ell_2} $
Show Answer
Answer:
Correct Answer: D
Solution:
- Change in length for both rods should be same $ \Delta {\ell_1}=\Delta {\ell_2} $ $ {\ell_1}{\alpha_1}\Delta T={\ell_2}{\alpha_2}\Delta T $ $ {\ell_1}{\alpha_1}={\ell_2}{\alpha_2} $
