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