Physics Elasticity Question 74
Question: The dimensions of four wires of the same material are given below. In which wire the increase in length will be maximum when the same tension is applied
[IIT 1981; NCERT 1976; MP PET/PMT 1998; CPMT 1983, 90; MP PMT 1992, 94, 97; MP PET 1989, 90, 99]
Options:
A) Length 100 cm, Diameter 1 mm
B) Length 200 cm, Diameter 2 mm
C) Length 300 cm, Diameter 3 mm
D) Length 50 cm, Diameter 0.5 mm
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Answer:
Correct Answer: D
Solution:
$ Y=\frac{F}{A}\ \frac{L}{A}\Rightarrow l\propto \frac{L}{A}\propto \frac{L}{\pi d^{2}} $ \ $ l\propto \frac{L}{d^{2}} $ [As F and Y are constant]The ratio of $ \frac{L}{d^{2}} $ is maximum for case
BETA
