AP EAMCET2008PhysicsMechanical Properties of Solids
A load of 1 ~kg weight is a attached to one end of a steel wire of area of cross-section 3 ~mm ^2 and Young's modulus 10¹¹ ~N / m ^2 . The other end is suspended vertically from a hook on a wall, then the load is pulled horizontally and released. When the load passes through its lowest position the fractional change in length is (g=10 ~m / s ^2 )
Options
- A0.3 10⁻⁴
- B0.3 10⁻³
- C0.3 10³
- D0.3 10⁴
Correct answer
A. 0.3 10⁻⁴
Step-by-step solution
aligned Y & = m g l A l l l & = m g A Y aligned aligned l l & = 1 10 3 10⁻⁶ 10¹¹ & =0.3 10⁻⁴ aligned