1. | \(\text{(stress)}^2 × \text{strain}\) | 2. | \(\text{stress} × \text{strain}\) |
3. | \(\dfrac12\times \text{stress} × \text{strain}\) | 4. | \(\text{stress} × \text{(strain)}^2\) |
When a metal wire elongates by hanging a load on it, the gravitational potential energy decreases.
1. | This energy completely appears as the increased kinetic energy of the block. |
2. | This energy completely appears as the increased elastic potential energy of the wire. |
3. | This energy completely appears as heat. |
4. | None of the above. |
A wire of length \(L\) and cross-sectional area \(A\) is made of a material of Young's modulus \(Y.\) It is stretched by an amount \(x.\) The work done is:
1. \(\dfrac{Y x A}{2 L}\)
2. \(\dfrac{Y x^{2} A}{L}\)
3. \(\dfrac{Y x^{2} A}{2 L}\)
4. \(\dfrac{2 Y x^{2} A}{L}\)
A \(5~\text{m}\) long wire is fixed to the ceiling. A weight of \(10~\text{kg}\) is hung at the lower end and is \(1~\text{m}\) above the floor. The wire was elongated by \(1~\text{mm}.\) The energy stored in the wire due to stretching is:
1. zero
2. \(0.05~\text J\)
3. \(100~\text J\)
4. \(500~\text J\)