The elastic energy stored in a wire of Young's Modulus \(Y\) is:

1. \(Y \times \dfrac{\left(\text{strain}\right)^{2}}{\text{volume}}\)

2. \(\text{stress} \times \text{strain} \times \text{volume}\)

3. \(\dfrac{\left(\text{strain}\right)^{2} \times \text{volume}}{2 Y}\)

4. \(\dfrac{1}{2} \times \text{stress} \times \text{strain} \times \text{volume}\)

Subtopic:  Potential energy of wire |
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A wire of natural length \(L\) and cross-sectional area \(A\) is made of a material of Young’s modulus \(Y.\) If the wire is stretched by an amount \(x,\) the energy stored in the wire is:
1. \( \dfrac{Y A x^{2}}{L}\) 2. \( \dfrac{Y A x^{2}}{2 L}\)
3. \(\dfrac{2 Y A x^{2}}{L}\) 4. \(\dfrac{Y A x^{2}}{L^{2}}\)
Subtopic:  Potential energy of wire |
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The energy density in a wire which is under stress is given by:
1. \({\Large\frac12}\text{(stress)}^2 \) 2. \({\Large\frac12}\text{(strain)}^2\)
3. \({\Large\frac12}\text{(stress)}\times\text{(strain)}\) 4. \({\Large\frac{1}{2}\frac{\text{(stress)}^2}{\text{strain}}}\)
Subtopic:  Potential energy of wire |
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Given below are two statements: 
Assertion (A): Identical springs of steel and copper are equally stretched. More work will be done on the steel spring.
Reason (R): Steel is more elastic than copper.
 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.
Subtopic:  Potential energy of wire |
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A wire of length \(L\) and cross-sectional area \(A\) is made of a material of Young’s modulus \(Y.\) On stretching the length of the wire by \(l,\) the elastic energy stored per unit volume is:
1. \(\dfrac{FA}{2L}\) 2. \(\dfrac{Fl}{2AL}\)
3. \(\dfrac{Fl}{AL}\) 4. \(\dfrac{FL}{Al}\)
Subtopic:  Potential energy of wire |
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The Young's modulus of a wire is \(Y.\) If the energy per unit volume is \(E,\) then the strain will be:

1. \(\sqrt{\dfrac{2 E}{Y}} \)                                         

2. \(\sqrt{2 E Y}\)

3. \(E Y\)                                             

4. \(\dfrac{E}{Y}\)

Subtopic:  Potential energy of wire |
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When a rubber is stretched, what happens to its energy?
1. Its kinetic energy increases.
2.  Its potential energy increases.
3. Its kinetic energy decreases.
4. Its potential energy decreases.
Subtopic:  Potential energy of wire |
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Work done by the restoring force in a wire within its elastic limit is \(-10~\text{J}\). The maximum amount of heat produced in the wire is: 
1. \(10~\text{J}\)
2. \(20~\text{J}\)
3. \(5~\text{J}\)
4. \(15~\text{J}\)
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