MCQ
Four identical rods are stretched by same force. Maximum extension is produced in
- A$L=10 cm , D=1 mm$
- ✓$L=100 cm , D=2 mm$
- C$L=200 cm , D=3 mm$
- D$L=300 cm , D=4 mm$
✓
Answer
Correct option: B.
$L=100 cm , D=2 mm$
(b) $l=\frac{F L}{\pi r^2 Y} \therefore l \propto \frac{L}{r^2}$Ratio of $\frac{L}{r^2}$ is maximum for wire in option (b).
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