MCQ
A rubber cord $10\, m$ long is suspended vertically. How much does it stretch under its own weight $($Density of rubber is $1500\, kg/m^3, Y = 5×10^8 N/m^2, g = 10 m/s^2$$)$
- ✓$15×10^{-4} m$
- B$7.5×10^{-4} m$
- C$12×10^{-4} m$
- D$25×10^{-4} m$
✓
Answer
Correct option: A.
$15×10^{-4} m$
a
(a) $l = \frac{{{L^2}dg}}{{2Y}} = \frac{{{{(10)}^2} \times 1500 \times 10}}{{2 \times 5 \times {{10}^8}}} = 15 \times {10^{ - 4}}m$
(a) $l = \frac{{{L^2}dg}}{{2Y}} = \frac{{{{(10)}^2} \times 1500 \times 10}}{{2 \times 5 \times {{10}^8}}} = 15 \times {10^{ - 4}}m$
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