Physics Elasticity Question 162
Question: A wire of cross section 4 mm2 is stretched by 0.1 mm by a certain weight. How far (length) will be wire of same material and length but of area 8 mm2 stretch under the action of same force
[Kerala PMT 2004]
Options:
A) 0.05 mm
B)0.10 mm
C) 0.15 mm
D)0.20 mm
E) 0.25 mm
Show Answer
Answer:
Correct Answer: A
Solution:
$ l=\frac{FL}{AY} $ \ $ l\propto \frac{1}{A} $ (F,L and Y are constant] $ \frac{l _{2}}{l _{1}}=\frac{A _{1}}{A _{2}}=\frac{4}{8}=\frac{1}{2} $
$ \Rightarrow l _{2}=\frac{l _{1}}{2}=\frac{0.1}{2}=0.05mm $
BETA
