Physics Elasticity Question 125
Question: Two wires of the same material have lengths in the ratio 1 : 2 and their radii are in the ratio $ 1:\sqrt{2} $ . If they are stretched by applying equal forces, the increase in their lengths will be in the ratio
[MP PET 1994]
Options:
A) $ 2:\sqrt{2} $
B) $ \sqrt{2}:2 $
C) 1 : 1
D) 1 : 2
Show Answer
Answer:
Correct Answer: C
Solution:
$ l=\frac{FL}{\pi r^{2}Y} $
$ \Rightarrow l\propto \frac{L}{r^{2}} $ (F and Y are constant) $ \frac{l _{1}}{l _{2}}=\frac{L _{1}}{L _{2}}{{\left( \frac{r _{2}}{r _{1}} \right)}^{2}}=\frac{1}{2}{{\left( \sqrt{2} \right)}^{2}} $ $ \frac{l _{1}}{l _{2}}=1:1 $
BETA
