MCQ
A spring with spring constant $k$ when stretched through $1 \mathrm{~cm}$, the potential energy is $U$. If it is stretched by $4 \mathrm{~cm}$. The potential energy will be
- A$4 U$
- B$8 U$
- ✓$16 \mathrm{U}$
- D$2 U$
✓
Answer
Correct option: C.
$16 \mathrm{U}$
(c) Potential energy $U=\frac{1}{2} k x^2$$\therefore U \propto x^2$ [if (k=$constant]If elongation made 4 times then potential energy will become 16 times.
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