MCQ
A wire fixed at the upper end stretches by length $l$ by applying a force $F$. The work done in stretching is
- A$\frac{F}{{2l}}$
- B$Fl$
- C$2Fl$
- ✓$\frac{{Fl}}{2}$
✓
Answer
Correct option: D.
$\frac{{Fl}}{2}$
d
$F_{a v}=\frac{0+F}{2}=\frac{F}{2}$
$F_{a v}=\frac{0+F}{2}=\frac{F}{2}$
$W=\left(\frac{0+F}{2}\right) \ell=\frac{F \ell}{2}$
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